JP2013136202A - Image forming apparatus, method for controlling image forming apparatus and control program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect a state of a resistance element whose temperature is low and resistance is high, which is arranged to prevent an inrush current and an electric resistance value becoming high as the temperature is low.SOLUTION: An image forming apparatus to which an NTC thermistor is arranged to prevent the inrush current includes: a motor in which an elastic component whose hardness increases in a low temperature is connected so as to become a load of movement; and a CPU101 for performing initialization control to operate the motor during power supply for initializing each part of the device. A control part determines that the load by the elastic component is high based on information showing a result controlled to operate the motor. The image forming apparatus is driven by power lower than usual, which is a low power driving state.

Description

  The present invention relates to an image forming apparatus, an image forming apparatus control method, and a control program, and more particularly to control of an image forming apparatus according to an operating environment.

  In recent years, there has been a tendency to digitize information, and image processing apparatuses such as printers and facsimiles used for outputting digitized information and scanners used for digitizing documents have become indispensable devices. Such an image processing apparatus is often configured as a multifunction machine that can be used as a printer, a facsimile, a scanner, or a copier by providing an imaging function, an image forming function, a communication function, and the like.

  On the other hand, an AC (Alternating Current) power supply unit for supplying power to such an image processing apparatus or the like, a PSU (Power Supply Unit), NTC (negative temporary temperature) in order to prevent an inrush current at the time of AC outlet plug-in. A technique for inserting a thermistor is already known.

  The NTC thermistor has a characteristic that the resistance value decreases according to the amount of current that flows. This is a characteristic that the resistance value is lowered by the heat generated by passing a current. Therefore, since the amount of heat is low at the time of AC outlet plug-in, the resistance value is high and plays a role of preventing inrush current. After a while, since the resistance value of the NTC thermistor decreases due to its own heat generation, the NTC thermistor behaves without generating wasteful power consumption due to the resistance value after playing the role of preventing inrush current.

  In such an inrush current prevention method using an NTC thermistor, the temperature of the NTC thermistor may be very low in a low temperature environment such as winter, and the resistance value may be high accordingly. In such a case, if the device is driven in a short period of time from the AC outlet plug-in, the NTC thermistor is not sufficiently warmed, and accordingly, the resistance value is high, so that a sufficient current cannot be supplied. There is a possibility that the apparatus may operate abnormally without being able to cope with a sudden increase in current consumption due to the apparatus operation.

  For example, when a plurality of motors are driven in the apparatus, there is a case where current supply to the motor cannot be sufficiently performed and the motor speed does not increase to an intended speed. In an inkjet image processing device, if sufficient current cannot be supplied to the main scanning motor that moves the inkjet head in the main scanning direction relative to the paper, the main scanning motor will run out of speed, causing paper jams in the device. Thus, there may be a case where erroneous detection occurs, for example, it is determined that the movement of the head in the main scanning direction is hindered.

  Such a problem can be dealt with, for example, by selecting an NTC thermistor that balances the prevention of inrush current, which is the original purpose of the NTC thermistor, and a resistance value that can cope with an increase in current consumption in a low temperature environment such as winter. Has been. However, it is difficult to select an appropriate NTC thermistor depending on the PSU characteristics.

  On the other hand, as a technique for dealing with such a problem, a method has been proposed in which the temperature of the NTC thermistor is detected to be very low and the resistance value is increased accordingly, and the current consumption is controlled according to the detection result. (For example, refer to Patent Document 1).

  In the technique disclosed in Patent Document 1, since a configuration for detecting the temperature of the NTC thermistor is newly required, the apparatus cost is increased. Such a problem can occur not only in the NTC thermistor but also in an apparatus in which a resistance element whose electric resistance value increases as the temperature increases is provided to prevent inrush current.

  The present invention has been made in view of the above circumstances, and is a resistance element provided for preventing an inrush current. The resistance element having a higher electrical resistance value as the temperature is lower has a lower temperature, and the resistance is lower. An object is to enable detection of a high state with a simple configuration.

  In order to solve the above-described problem, an aspect of the present invention is an image forming apparatus in which a resistance element whose electric resistance value increases as the temperature decreases is provided to prevent inrush current, and the elasticity increases in hardness at low temperatures. A power unit connected so that a part can be a load of movement; and an initialization control unit that performs initialization control to initialize each part of the apparatus by operating the power unit when power is turned on. The unit determines that the load due to the elastic component is high based on information indicating a result of controlling the power unit to operate, and determines that the load due to the elastic component is high. A low power driving state in which driving is performed with lower power than usual is characterized.

  Another aspect of the present invention is a method for controlling an image forming apparatus in which a resistance element whose electrical resistance value increases as the temperature decreases is provided to prevent inrush current. Based on the information indicating the result of performing control to operate the power unit by performing initialization control to initialize each part of the device by operating the power unit connected so that the elastic part to be increased can be a load of movement When it is determined that the load due to the elastic component is high and it is determined that the load due to the elastic component is high, the image forming apparatus is set in a low power driving state in which the image forming apparatus is driven with lower power than usual.

  Still another embodiment of the present invention is a control program for an image forming apparatus in which a resistance element whose electric resistance value increases as the temperature decreases is provided to prevent inrush current. Information indicating the result of controlling the operation of the power unit and the step of performing initialization control to initialize each part of the device by operating the power unit connected so that the elastic component that increases can be a load of movement And determining that the load by the elastic component is high, and when determining that the load by the elastic component is high, setting the image forming apparatus in a low power driving state in which the image forming apparatus is driven with lower power than usual. And an image forming apparatus.

  According to the present invention, a resistance element provided for preventing an inrush current can be detected with a simple configuration that a resistance element having a higher electrical resistance value at a lower temperature has a lower temperature and a higher resistance. can do.

1 is a perspective view illustrating an overall configuration of an image forming apparatus according to an embodiment of the present invention. 1 is a side view illustrating an overall configuration of an image forming apparatus according to an embodiment of the present invention. 1 is a top view illustrating an overall configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a diagram illustrating a configuration of a supply pump unit of the image forming apparatus according to the embodiment of the present invention. FIG. 3 is a block diagram illustrating a control configuration of the image forming apparatus according to the embodiment of the present invention. 1 is a diagram illustrating a configuration of a PSU of an image forming apparatus according to an embodiment of the present invention. 3 is a flowchart showing an operation at power-on of the image forming apparatus according to the embodiment of the present invention. 6 is a flowchart illustrating a load determination operation of the image forming apparatus according to the exemplary embodiment of the present invention. 6 is a flowchart illustrating a load determination operation of the image forming apparatus according to the exemplary embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the present embodiment, in an inkjet printer that is an image forming apparatus, the temperature of an NTC (negative temperature coefficient) thermistor provided for preventing inrush current in an AC (Alternating Current) power supply unit that supplies power to each part of the apparatus is low, A configuration for detecting a high resistance state will be described.

  FIG. 1 is a perspective view showing an image forming apparatus according to the present embodiment. In FIG. 1, for the sake of explanation, a part of the apparatus is shown through a broken line. As shown in FIG. 1, the image forming apparatus according to the present embodiment is detachably attached to the apparatus main body 1, a paper feed tray 2 for loading paper attached to the apparatus main body 1, and the apparatus main body 1. And a paper discharge tray 3 for stocking paper on which images are recorded (formed).

  On one end of the entire surface of the apparatus main body 1 (on the side of the paper supply / discharge tray section), there is a cartridge mounting portion 4 for mounting an ink cartridge that protrudes forward from the apparatus main body 1 and is lower than the upper surface. The upper surface of the cartridge mounting unit 4 is an operation / display unit 5 provided with operation buttons, a display, and the like. The cartridge mounting portion 4 includes a plurality of ink cartridges 10k each containing recording liquids (inks) of different colors, for example, black (K) ink, cyan (C) ink, magenta (M) ink, and yellow (Y) ink. 10c, 10m, and 10y (hereinafter collectively referred to as the ink cartridge 10) are inserted.

  Each of the ink cartridges 10k, 10c, 10m, and 10y includes an ID chip that stores ink information, and is configured to be inserted from the side surface side of the apparatus main body 1 toward the rear side. A cover (cartridge cover) 6 that is opened when the ink cartridge 10 is attached or detached is provided on the entire surface of the cartridge mounting portion 4 so as to be opened and closed. In FIG. 1, the cover 6 is shown in a transparent manner.

  In the operation / display unit 5, the remaining amounts of the ink cartridges 10k, 10c, 10m, and 10y for each color are near-end at an arrangement position corresponding to the mounting position (arrangement position) of the ink cartridges 10k, 10c, 10m, and 10y for each color. The remaining amount display portions 11k, 11c, 11m, and 11y for each color for displaying the end are arranged. Further, the operation / display unit 5 is also provided with a power button 12, a paper feed / print resume button 13, and a cancel button 14.

  FIG. 2 is a side view showing a mechanism inside the image forming apparatus according to this embodiment, and FIG. 3 is a top view showing a mechanism inside the image forming apparatus according to this embodiment. As shown in FIG. 3, a guide lot 31 and a stay 32, which are guide members horizontally mounted on the left and right side plates 21A and 21B constituting the frame 21 of the entire apparatus, can slide the carriage 33 in the main scanning direction. Hold. The carriage 33 is moved and scanned in an arrow direction (carriage scanning direction: main scanning direction) in FIG. 3 by a main scanning motor (not shown).

  In the carriage 33, a plurality of recording heads 34, which are ink jet heads that are droplet ejection heads for ejecting ink droplets, are arranged with a plurality of nozzles along the main scanning direction, and the ink droplet ejection direction is downward. It is attached towards. The recording head 34 includes a recording head 34y that discharges yellow (Y) droplets, a recording head 34c that discharges cyan (C) droplets, a recording head 34m that discharges magenta (M) droplets, and black (Bk). ), And a recording head 34k for discharging droplets.

  In the following description, when the recording head is referred to as “recording head 34”, the colors are not distinguished. The head configuration is not limited to this example, and the head configuration can be configured by using one or a plurality of recording heads having one or a plurality of nozzle rows that eject droplets of one or a plurality of colors.

  The droplet discharge head constituting the recording head 34 includes a piezoelectric actuator such as a piezoelectric element, a thermal actuator that uses a phase change caused by liquid film boiling using an electrothermal transducer such as a heating resistor, and a metal phase caused by a temperature change. A shape memory alloy actuator using a change, an electrostatic actuator using an electrostatic force, or the like provided as pressure generating means for generating a pressure for discharging a droplet can be used.

  The carriage 33 is mounted with head tanks 35y, 35m, 35c, and 35k (hereinafter collectively referred to as head tanks 35) for supplying the inks of the respective colors to the recording head 34. The head tank 35 is replenished and supplied with ink from the ink cartridge 10 of each color described above via the ink supply tube 37 of each color. That is, the ink cartridge 10 functions as an ink supply unit.

  Here, the ink cartridge 10 is accommodated in the cartridge mounting portion 4, and a supply pump unit 23 for feeding the ink in the ink cartridge 10 is attached to the cartridge mounting portion 4 as shown in FIG. Yes. Further, the ink supply tube 37 from the ink cartridge mounting portion 4 to the head tank 35 is fixed and held on the rear plate 21C constituting the frame 21 by using the main body side holder 25 in the course of turning, and further, the carriage 33 The upper part is also fixed using the fixing rib 26.

  FIG. 4 is a diagram illustrating an internal configuration of the supply pump unit 23. FIG. 4 shows a supply pump unit 23a which is a configuration corresponding to an ink cartridge for one color among the internal configurations of the supply pump unit 23. As shown in FIG. 4, the supply pump unit 23 a includes a cartridge connection pin 231, an in-unit tube 232, a supply roller 233, and a supply roller drive motor 234.

  The cartridge connection pin 231 is a tubular component that is connected to the ink cartridge 10 and guides the ink in the ink cartridge 10 to the in-unit tube 232. The in-unit tube 232 is wound around the supply roller 233 in the supply pump unit 23a.

  As the supply roller 233 rotates, the ink filled in the in-unit tube 232 is sequentially conveyed from the cartridge connection pin 231 side to the supply tube 37 side and sent out. The supply roller drive motor 234 is a motor for driving the supply roller 233 to rotate.

  As shown in FIG. 2, the sheet 42 is separated from the bottom plate one by one as a sheet feeding unit which is a feeding unit for feeding the sheets 42 stacked on the bottom plate (sheet stacking unit) 41 of the sheet feeding tray 2. A sheet feeding roller 43 to be fed and a separation pad 44 made of a material having a large friction coefficient are provided opposite to the sheet feeding roller 43, and the separation pad 44 is urged toward the sheet feeding roller 43 side.

  In order to feed the paper 42 fed from the paper feeding unit to the lower side of the recording head 34, a guide 45 for guiding the paper 42, a counter roller 46, a transport guide member 47, and a tip pressure roller 49 are provided. In addition to a pressing member 48, a feeding belt 51, which is a feeding unit for electrostatically attracting the fed paper 42 and transporting it at a position facing the recording head 34, is provided.

  The conveyor belt 51 is an endless belt, and is configured to wrap around the conveyor roller 57 and the tension roller 58 and circulate in the belt conveyance direction (sub-scanning direction). This transport belt 51 is, for example, a layer that becomes a sheet adsorbing surface formed of a pure resin material having a thickness of about 40 μm that is not subjected to resistance control, for example, ETFE pure material, and resistance control by carbon with the same material as this surface layer. And performed layers (medium resistance layer, ground layer).

  In order to charge the surface of the conveyor belt 51, a charging roller 56 is provided as a charging unit. The charging roller 56 is disposed so as to come into contact with the surface layer of the conveyor belt 51 and rotate following the rotation of the conveyor belt 51, and a predetermined pressing force is applied to both ends of the shaft as a pressing force. The transport roller 52 also functions as an earth roller, and is in contact with the middle resistance layer (back layer) of the transport belt 51 and is grounded. Further, a guide member 61 is disposed on the back side of the conveyance belt 51 with respect to a printing area by the recording head 34. The guide member 61 has an upper surface that protrudes toward the recording head 34 from the tangent line of the two rollers (the conveyance roller 52 and the tension roller 58) that support the conveyance belt 51, thereby maintaining high-precision flatness of the conveyance belt 51. Like to do.

  As shown in FIG. 2, a double-sided paper feeding unit 81 is detachably mounted on the back surface of the apparatus main body 1. The double-sided paper feeding unit 81 takes in the paper 42 returned by the reverse rotation of the transport belt 51, reverses it, and feeds the paper again between the tip pressure roller 55 and the transport belt 51. A manual paper feed unit 82 is provided on the upper surface of the double-sided paper feed unit 81.

  As shown in FIG. 3, a maintenance / recovery mechanism 91 including a recovery means for maintaining and recovering the nozzle state of the recording head 34 is disposed in a non-printing area on one side of the carriage in the main scanning direction. . The maintenance / recovery mechanism 91 includes cap members 92a, 92b, 92c, and 92d (hereinafter collectively referred to as a cap 92) for capping each nozzle surface of the recording head 34, and a blade member for wiping the nozzle surface. A wiper blade 93 and a discharge receiver 94 for receiving droplets when performing state maintenance discharge for discharging droplets that do not contribute to recording in order to discharge the thickened recording liquid are included. Here, the cap 92a is a suction and moisture retention cap, and the other caps 92b to 9d are moisture retention caps.

  In addition, the non-printing area on the other side in the scanning direction of the carriage 33 receives liquid droplets when performing state maintenance discharge in which liquid droplets that do not contribute to recording are discharged in order to discharge the recording liquid thickened during recording or the like. A state maintaining discharge receiver 98 is disposed, and the state maintaining discharge receiver 98 is provided with an opening 99 along the nozzle row direction of the recording head 34.

  In the ink jet recording apparatus configured as described above, the sheets 42 are separated and fed one by one from the sheet feeding tray 2, and the sheet 42 fed substantially vertically upward is guided by the guide 45. The paper 42 guided by the guide 45 is further transported by being sandwiched between the transport belt 51 and the counter roller 52, guided at the front end by the transport guide 53, and pressed against the transport belt 51 by the front end pressure roller 55.

  When the paper 42 is pressed against the conveyance belt 51, a positive output and a negative output are alternately applied to the charging roller 56 from the AC bias supply unit by a control unit (not shown), that is, an alternating voltage is applied. In the charging voltage pattern in which 51 alternates, that is, in the sub-scanning direction that is the circumferential direction, plus and minus are alternately charged in a band shape with a predetermined width. When the sheet 42 is fed onto the conveyance belt 51 charged alternately with plus and minus, the sheet 42 is attracted to the conveyance belt 51, and the sheet 42 is conveyed in the sub-scanning direction by the circular movement of the conveyance belt 51.

  When the sheet 42 is sucked and conveyed by the conveyance belt 51, the recording head 34 is driven according to the image signal while the carriage 33 is moved, thereby ejecting ink droplets onto the stopped sheet 42. An image for a line is recorded, and after the paper 42 is conveyed by a predetermined amount, the next line is recorded. Upon receiving a recording end signal or a signal that the trailing edge of the paper 42 has reached the recording area, the image forming apparatus ends the recording operation and discharges the paper 42 to the paper discharge tray 3.

  When waiting for printing (recording), the carriage 33 is moved toward the maintenance / recovery mechanism 91, and the recording head 34 is capped by the cap 92. Thereby, the nozzle is kept in a wet state, and discharge failure due to ink drying can be prevented. Further, the recording liquid is sucked from the nozzle by a suction pump (not shown) with the recording head 34 being capped by the cap 92 (hereinafter referred to as “nozzle suction” or “head suction”), and the thickened recording liquid and bubbles are discharged. Recovery operation is executed. Further, a state maintaining discharge operation for discharging ink not related to recording is performed before the start of recording or during recording. As a result, stable ejection performance of the recording head 34 can be maintained.

  Next, a control configuration of the image forming apparatus according to the present embodiment will be described with reference to FIG. As shown in FIG. 5, the control unit 100 of the image forming apparatus according to the present embodiment also serves as a unit that controls the sheet conveyance operation and the recording head moving operation, and controls the overall operation of the CPU (Central Processing). (Unit) 101, a program executed by CPU 101, ROM (Read Only Memory) 102 for storing other fixed data, RAM (Random Access Memory) 103 which is a volatile memory for temporarily storing image data, etc. NVRAM (Non-Volatile RAM) 104, which is a rewritable nonvolatile storage medium for retaining data even while data is shut off, memory, image processing for performing various signal processing, rearrangement, etc. on image data, and others Control the entire device And a ASIC105 for processing because the input and output signals of.

  Further, the control unit 100 generates a drive waveform for driving the recording head 34 of the host I / F 106 and carriage 33 for transmitting and receiving data and signals to and from the host side, and pressure generating means for the recording head 34. The head control unit 107 that outputs image data to be selectively driven to the head driver 112, the main scanning motor driving unit 108 for driving the main scanning motor 113, and the sub-scanning motor 114 for driving the sub-scanning motor 114. I / O 111 for inputting a detection pulse from a scanning motor driving unit 109, an AC bias supply unit 110 for supplying an AC bias to the charging roller 56, a linear encoder 115, a wheel encoder 116, and other various sensors. Etc. The control unit 100 is connected to an operation panel 117 and an external storage device 118 for inputting and displaying information necessary for the apparatus.

  Here, the control unit 100 hosts print data generated by a host printer driver such as an information processing apparatus such as a personal computer, an image reading apparatus such as an image scanner, and an imaging apparatus such as a digital camera via a cable or a network. Received by the I / F 106. Also, the host I / F 106 receives commands from the host PC terminal.

  Then, the CPU 101 of the control unit 100 reads out and analyzes the print data in the reception buffer included in the host I / F 106, causes the ASIC 105 to perform necessary image processing, data rearrangement processing, and the like, and causes the head control unit 107 to execute. Forward. Image data and drive waveforms are output from the head controller 107 to the head driver 112 at a required timing.

  The generation of dot pattern data for image output may be performed by storing font data in the ROM 102, for example, or image data is developed into bitmap data by a host-side printer driver and transferred to this apparatus. You may do it. Here, the printer driver is used.

  The drive waveform generation unit of the head control unit 107 includes a D / A converter and an amplifier that perform D / A conversion on drive pulse pattern data stored in the ROM 102 and read by the CPU, and includes one drive pulse or a plurality of drive pulses. A drive waveform composed of drive pulses is output to the head driver 112.

  The head driver 112 generates a drive pulse that constitutes a drive waveform provided from the drive waveform generation unit of the head control unit 107 based on image data (dot pattern data) corresponding to one row of the recording head 34 that is input serially. The recording head 34 is driven by selectively applying to the pressure generating means of the recording head 34.

  The head driver 112 converts, for example, a shift register for inputting a clock signal and serial data as image data, a latch circuit for latching a registration value of the shift register with a latch signal, and level conversion of an output value of the latch circuit. A level conversion circuit (level shifter) and an analog switch array (switch means) whose on / off is controlled by this level shifter, etc., and the required drive pulse included in the drive waveform by controlling the on / off of the analog switch array Is selectively applied to the pressure generating means of the recording head 34.

  FIG. 6 is a diagram schematically illustrating a configuration of a PSU (Power Supply Unit) 200 that supplies power to each unit of the image processing apparatus according to the present embodiment. As shown in FIG. 6, the PSU 200 according to this embodiment includes an AC outlet 201, an NTC thermistor 202, and an AC voltage conversion transformer 203.

  The AC outlet 201 supplies commercial AC power to the PSU 200 by being connected to commercial power. The NTC thermistor 202 is a resistance element whose electrical resistance value increases as the temperature decreases, and is provided to prevent an inrush current when the AC outlet 201 is connected to a commercial power source.

  The resistance value of the NTC thermistor 202 decreases when the AC outlet 201 is connected to a commercial power source and the temperature rises due to the flow of current. Due to such characteristics, the NTC thermistor 202 functions as a resistance only when the AC outlet 201 is connected to a commercial power source to prevent an inrush current, and thereafter functions as a current path through which a current flows with a low resistance value. The AC voltage conversion transformer 203 converts the voltage of the power supplied via the NTC thermistor 202 according to the number of turns of the coil.

  In such a configuration, the image forming apparatus according to the present embodiment has a simple configuration in which the temperature of the NTC thermistor 202 provided in the PSU 200 is very low, and thus the resistance value is high enough to hinder the operation. The gist is to detect with.

  In the present embodiment, the temperature of the NTC thermistor 202 is low based on information that can be detected by a conventionally mounted sensor without providing a special sensor or the like to detect a state where the temperature of the NTC thermistor 202 is low. Detect state.

  For example, the components constituted by the elastic members such as the conveyance belt 51, the ink supply tube 37, and the unit inner tube 232 are reduced in hardness when the temperature is high, and are increased when the temperature is low. If the hardness of the conveyor belt 51 is high, the resistance to rotation of the conveyor roller 57 increases, and when the sub-scanning motor 115 is driven by the same electric power to rotate the conveyor roller 57, the temperature is higher. It is conceivable that the conveyance rollers 57 and the sub-scanning motor 115 rotate slowly. Further, when the transport roller 57 is rotated at a constant speed, a larger current is required than when the temperature is high.

  Similarly, if the hardness of the ink supply tube 37 is high, the resistance to movement of the carriage 33 increases, and when the main scanning motor 113 is driven by the same power, the movement speed of the carriage 33 is slower than when the temperature is high. It is possible to become. Further, when the carriage 33 is moved at a constant speed, a larger current is required than when the temperature is high.

  Further, if the unit tube 232 has a high hardness, the resistance against rotation of the supply roller 233 increases, and when the supply roller drive motor 234 is moved at a constant speed, a larger current is required than when the temperature is high. Become. That is, the main scanning motor 113, the sub-scanning motor 114, and the supply roller 233 are power units, and are connected so that an elastic component whose hardness increases at a low temperature can be a load of movement.

  In the present embodiment, based on such a concept, a state where the temperature of the NTC thermistor 202 is low is detected based on the control state of other parts of the image forming apparatus. The operation of the image forming apparatus according to this embodiment will be described below.

  FIG. 7 is a flowchart showing the operation of the image forming apparatus according to this embodiment when the power is turned on. As shown in FIG. 7, the AC outlet 201 is connected to a commercial power source, the power source is turned on, and an initial operation is started under the control of the CPU 101 (S701). That is, here, the CPU 101 functions as an initialization control unit.

  In the initial operation, a sub-scanning initial operation for rotating the conveyor belt 51 in a predetermined period is executed. The CPU 101 is based on the detection pulse of the wheel encoder 116 and the value of the driving current for driving the sub-scanning motor 114 at a predetermined rotational speed, that is, information indicating the result of operating the power unit in the initialization control. The operation load in the sub-scanning direction is determined (S702).

  As a result of the determination in S702, if it is determined that the operation load in the sub-scanning direction is high (S702 / YES), that is, if it is determined that the hardness of the conveyor belt 51 is high and the temperature is low, the CPU 101 determines that the NTC thermistor. It is determined that the temperature of 202 is also low, and the apparatus is set in a low current drive state (S703).

  Here, the low current driving state of the apparatus is a state in which the main scanning motor 113 and the sub-scanning motor 114 are rotated at a low speed to reduce the number of pages that can be formed and output per unit time PPM (Page Per Minutes). In this case, the current value required to rotate the main scanning motor 113 and the sub-scanning motor 114 becomes low. Therefore, since the temperature of the NTC thermistor 202 is low and the resistance value is high, even if a normal current is not supplied from the PSU 200 to each part of the apparatus, it is possible to prevent malfunction of each part of the apparatus. it can.

  As a result of the determination in S702, when it is determined that the load in the sub-scanning direction is normal (S702 / NO), that is, when it is determined that the hardness of the conveyor belt 51 is normal, the CPU 101 next performs main processing. In the scanning initial operation, the same determination is made (S704).

  The main scanning initial operation is an operation for placing the carriage 33 at the home position. The CPU 101 drives the main scanning motor 113 to move the carriage 33, and also detects the detection pulse of the linear encoder 115 and the value of the driving current for driving the main scanning motor 113 at a predetermined rotational speed, that is, initialization control. The operation load in the main scanning direction is determined based on the information indicating the result of operating the power unit at (S704).

  As a result of the determination in S704, when it is determined that the operation load in the main scanning direction is high (S704 / YES), that is, when it is determined that the hardness of the ink supply tube 37 is high and the temperature is low, the CPU 101 determines that the NTC It is determined that the temperature of the thermistor 202 is also low, and the apparatus is set in a low current driving state (S703).

  As a result of the determination in S704, if it is determined that the load in the main scanning direction is normal (S704 / NO), that is, if it is determined that the hardness of the ink supply tube 37 is normal, the CPU 101 next The same determination is performed in the initial operation of the supply pump unit 23 (S705).

  The initial operation of the supply pump unit 23 is an operation of conveying ink from the ink cartridge 10 side to the ink supply tube 37 side by rotationally driving the supply roller 233. The CPU 101 controls an IC (Integrated Circuit) (not shown) for rotationally driving the supply roller 233 to rotationally drive the supply roller 233, and at the same time, a drive current for driving the supply roller drive motor 234 at a predetermined rotational speed. Based on the value, that is, information indicating the result of operating the power unit in the initialization control, the operating load of the supply pump unit 23a is determined (S705).

  As a result of the determination in S705, if it is determined that the operating load of the supply pump unit 23a is high (S705 / YES), that is, if the hardness of the in-unit tube 232 is high and the temperature is determined to be low, the CPU 101 It is determined that the temperature of the NTC thermistor 202 is also low, and the apparatus is set in a low current drive state (S703).

  As a result of the determination in S705, when it is determined that the operating load of the supply pump unit 23a is normal (S705 / NO), that is, when it is determined that the hardness of the in-unit tube 232 is normal, the CPU 101 determines that the NTC It is determined that the temperature of the thermis 202 is not low and a normal current is supplied, and the apparatus is set in a normal driving state (S706).

  Next, details of the determinations in S702, S704, and S705 will be described. In the determinations in S702 and S704, the CPU 101 can detect the rotation speeds of the sub-scanning motor 114 and the main scanning motor 113 based on the detection pulses of the hall encoding 116 and the linear encoder 115, respectively. FIG. 8 shows an operation in the case of making a determination based on the detection result.

  As shown in FIG. 8, when the determination is made based on the detection pulse from each encoder, the CPU 101 drives the sub-scanning motor 114 and the main scanning motor 113 with constant current (S801). The current value for driving each motor in S801 is, for example, a specified current value used when driving each motor in normal operation.

  When the motor is driven at a constant current, detection pulses are output from the linear encoder 115 and the wheel encoder 116 at intervals corresponding to the rotation speed, and are acquired via the I / O 111. The CPU 101 counts the encoder signal (S802) and calculates the rotation speed of each motor (S803).

  Since the motor is driven with a constant current in S801, when the hardness of the transport belt 51 and the ink supply tube 37 is high, the speed calculated in S803 is low. The CPU 101 compares the speed calculated in S803 with a predetermined threshold (S804), and determines that the load is high (S805) if the calculation result is equal to or less than the threshold (S804 / YES). On the other hand, if the calculation result exceeds the threshold (S804 / NO), it is determined that the load is in a normal state (S806).

  In FIG. 8, since each motor is driven at a constant current, if the conveyance belt 51 and the ink supply tube 37 are in a high hardness state, the criterion is that the speed calculated based on the encoder output is low. On the other hand, there is also a method of rotating each motor at a specified speed by performing feedback control based on the encoder output. Such a method can be used in the determination of S702, S704, and S705. An example of such a case is shown in FIG.

  As shown in FIG. 9, the CPU 101 feedback-controls the drive current value based on the detection pulses of the linear encoder 115, the wheel encoder 116, and the encoder (not shown) of the supply roller drive motor 234, thereby determining a predetermined predetermined value. Each motor is driven at a speed (S901).

  If the current supplied to each motor exceeds the predetermined threshold and is detected as an overcurrent by performing the drive control in S901 (S902 / YES), the CPU 101 loads the respective motors, that is, the conveyance belt 51. Then, it is determined that the hardness of the ink supply tube 37 and the unit inner tube 232 is high (S903). On the other hand, if no overcurrent is detected (S902 / NO), the CPU 101 determines that the load on each motor is in a normal state (S904).

  In S902, for example, a main scanning motor driving unit 108 that drives the main scanning motor 113, a sub scanning motor driving unit 109 that drives the sub scanning motor 114, and an IC that rotationally drives the supply roller 233 are applied. If the configuration is such that an overcurrent detection signal is output when the current value exceeds a predetermined threshold, the CPU 101 can make the determination in S902 based on the overcurrent detection signal.

  As described above, in the image forming apparatus according to this embodiment, in the initial operation after the power is turned on, components such as the conveyance belt 51, the ink supply tube 37, the unit inner tube 232, and the like that increase in hardness at low temperatures can become resistance. The temperature is determined based on the operation status of the operation units such as the main scanning motor 113, the sub-scanning motor 114, and the supply roller 233 connected in this manner, and the resistance value corresponding to the temperature of the NTC thermistor 202 based on the determination result Judging.

  The operation status of the drive unit described above is information that can be detected by a function that has been conventionally installed in an image forming apparatus. Therefore, in the image forming apparatus according to the present embodiment, it is possible to detect a state where the temperature of the NTC thermistor provided for preventing inrush current is low and the resistance is high with a simple configuration.

  In the above-described embodiment, the case where the temperature of the NTC thermistor is low and it is determined that the resistance is high is described as an example in which the image forming apparatus is in a low current driving state. As described above, this is a control that takes into account that sufficient power is not supplied by the resistance of the NTC thermistor. Therefore, the state is not limited to low current driving, and may be in a state corresponding to driving with lower power than usual, such as low voltage driving.

DESCRIPTION OF SYMBOLS 1 Apparatus main body 2 Paper feed tray 3 Paper discharge tray 4 Cartridge mounting part 5 Display part 6 Cover 10, 10k, 10c, 10m, 10y Ink cartridge 11, 11k, 11c, 11m, 11y Remaining capacity display part 12 Power button 13 Resume printing Button 14 Cancel button 21 Frame 21A, 21B Side plate 21C Rear plate 23 Supply pump unit 25 Main body side holder 26 Fixing rib 31 Guide lot 32 Stay 33 Carriage 34, 34k, 34c, 34m, 34y Recording head 35, 35k, 35c, 35m, 34y Head tank 37 Ink supply tube 41 Bottom plate 42 Paper 43 Paper feed roller 44 Separation pad 45 Guide 46 Counter roller 47 Transport guide member 48 Member 49 Tip pressure roller 51 Transport belt 52 Transport roller 52 Counter roller 53 Transport guide 5 Tip pressure roller 56 Charging roller 57 Transport roller 58 Tension roller 61 Guide member 81 Double-sided paper feed unit 82 Paper feed unit 91 Maintenance recovery mechanism 92, 92a, 92b, 92c, 92d Cap 93 Wiper blade 94 Discharge receiver 99 Opening 100 Control unit 101 CPU
102 ROM
103 RAM
104 NVRAM
105 ASIC
106 Host I / F
107 Engine control unit 108 Main scanning motor driving unit 109 Sub scanning motor driving unit 110 AC bias supply unit 111 I / O
112 Head driver 113 Main scanning motor 114 Sub scanning motor 115 Linear encoder 116 Wheel encoder 117 Operation panel 118 External storage device 200 PSU
201 AC outlet 202 NTC thermistor 203 AC voltage conversion transformer

JP 2011-005740 A

Claims (8)

An image forming apparatus in which a resistance element whose electric resistance value increases as temperature decreases is provided to prevent inrush current,
A power unit connected so that an elastic part whose hardness increases at a low temperature can be a load of movement;
An initialization control unit for performing initialization control for operating the power unit when power is turned on to initialize each unit of the device,
The initialization control unit
Based on the information indicating the result of controlling to operate the power unit, it is determined that the load by the elastic component is high,
When it is determined that the load due to the elastic component is high, the image forming apparatus is placed in a low power driving state in which the image forming apparatus is driven with lower power than usual. The power unit is a motor that generates a rotational force,
The initialization control unit has a high load due to the elastic component based on a comparison result between a rotational speed of the power unit detected when the power unit is rotationally driven with a predetermined electric power and a predetermined threshold value. The image forming apparatus according to claim 1, wherein the determination is made. The power unit is a motor that generates a rotational force,
The initialization control unit determines that the load due to the elastic component is high based on a comparison result between a power required when the power unit is rotationally driven at a predetermined rotational speed and a predetermined threshold value. The image forming apparatus according to claim 1, wherein: The elastic component includes a conveyance unit that conveys a sheet that is an image formation output target in the image forming apparatus,
The image forming apparatus according to claim 1, wherein the power unit includes a motor that rotates the conveyance unit. The elastic component includes a tube that supplies ink to a recording head that discharges ink to paper in the image forming apparatus,
The image forming apparatus according to claim 1, wherein the power unit includes a motor that generates power for moving the recording head in a direction orthogonal to a direction in which the sheet is conveyed. apparatus. The elastic component includes a tube inside a pump that acquires and supplies ink from an ink cartridge to a tube that supplies ink to a recording head that discharges ink to paper in the image forming apparatus,
The image forming apparatus according to claim 1, wherein the power unit includes a motor that generates power for compressing a tube inside the pump and transporting ink. A control method for an image forming apparatus in which a resistance element whose electrical resistance value increases as temperature decreases is provided to prevent inrush current,
When the power is turned on, initialization control is performed to initialize each part of the device by operating the power unit connected so that the elastic part whose hardness increases at low temperatures can be a load of movement,
Based on the information indicating the result of controlling to operate the power unit, it is determined that the load by the elastic component is high,
A control method for an image forming apparatus, characterized in that when it is determined that a load due to the elastic component is high, the image forming apparatus is set in a low power driving state in which the image forming apparatus is driven with lower power than usual. A control program for an image forming apparatus in which a resistance element whose electrical resistance value increases as temperature decreases is provided to prevent inrush current,
A step of performing initialization control for initializing each part of the apparatus by operating a power unit connected so that an elastic part whose hardness increases at a low temperature can be a load of movement when the power is turned on;
Determining that the load from the elastic component is high based on information indicating a result of controlling the power unit to operate;
An image forming apparatus that causes the image forming apparatus to execute a step of setting the image forming apparatus in a low power driving state in which the image forming apparatus is driven with lower power than normal when it is determined that the load due to the elastic component is high. Control program.

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