JP2007329041A - Heating device, image forming device and diagnostic method of heating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make it possible to detect an irregularity when heating of a heating object is started. <P>SOLUTION: A controlling unit calculates a value of a temperature rising speed S of a heating roll and compares with a status responding table and judges if the value of the temperature rising speed S is 3°C/second or less or between 3°C/second and 10°C/second or between 10°C/second and 13°C/second, and if it is between 10°/second and 13°C/second, the unit judges it as a normal state and makes a fixed temperature controlling treatment, and in other cases, irregularities are displayed according to their types. The controlling unit inputs the judgement results (information) in a memory unit 52 and after a power source is switched on and if information on the irregular temperature rising speed is available in the memory unit 52, the irregularities are displayed according to their types without making the fixed temperature control treatment. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a heating apparatus that heats by energization, an image forming apparatus, and a diagnostic method for the heating apparatus.

2. Description of the Related Art An image forming apparatus having a fixing device that heats a toner image on a sheet by a heating body and fixes the toner image on the sheet is known.
In this type of image forming apparatus, the temperature rise rate of the heating body is calculated after the heating body temperature exceeds the target fixing temperature, and when the calculated value exceeds a certain value, the energization to the heating body is stopped and the heating body is heated. It is known that the body is prevented from being damaged due to an abnormally high temperature (see Patent Document 1).

JP 2000-137394 A

  However, the above-described conventional example only discloses a technique for detecting an abnormality when the temperature of the heating body exceeds the target fixing temperature for the purpose of preventing damage to the heating body due to an abnormal temperature rise. No consideration is given to the abnormalities at the start of heating.

  An object of the present invention is to provide a heating apparatus, an image forming apparatus, and a diagnostic method for a heating apparatus that can detect an abnormality at the start of heating of a heating body.

In order to achieve the above object, the first feature of the present invention is that a heating body that is heated by energization, a detecting means that detects a temperature rise of the heating body, and the temperature of the heating body is a predetermined set temperature. The heating apparatus includes a determination unit that determines presence / absence of an abnormality based on a result detected by the detection unit, and an output unit that outputs information based on the determination result of the determination unit. That is, an abnormality can be detected at the start of heating of the heating body, and the user can grasp the abnormality at the start of heating of the heating body from the information output by the output means.
The target detected by the detection unit may be, for example, a temperature increase rate, a temperature increase rate, a temperature difference between detection timings, or a temperature between detection timings.

  Suitably, the said determination means each determines the presence or absence of multiple types of abnormality based on the value of the temperature rise of the said heating body. That is, the user can distinguish and recognize a plurality of types of abnormalities based on the temperature rise value.

  Preferably, the apparatus further includes a storage unit that stores a determination result of the determination unit, and a control unit that controls energization of the heating body based on the determination result stored in the storage unit.

  Preferably, the apparatus further includes removal means for removing the determination result stored in the storage means.

  Preferably, the determination means determines that there is an abnormality in energization of the heating body when the value of the temperature rise of the heating body is less than a set value and not more than a predetermined value.

  Preferably, the determination means determines that the heating body is abnormal when the value of the temperature rise of the heating body is less than a set value and greater than a predetermined value.

  Preferably, the determination means determines that the heating body is abnormal when the value of the temperature rise of the heating body is larger than a set value and larger than a predetermined value.

  The second feature of the present invention is that a fixing device for fixing a developer image on a recording medium to a recording medium by a heating body heated by energization, and a detecting means for detecting a temperature rise of the heating body, A determination unit that determines whether there is an abnormality based on a result detected by the detection unit before the temperature of the heating body reaches a predetermined set temperature; and an output unit that outputs information based on the determination result of the determination unit And an image forming apparatus.

  Suitably, the said determination means each determines the presence or absence of multiple types of abnormality based on the value of the temperature rise of the said heating body.

  Preferably, the apparatus further includes a storage unit that stores a determination result of the determination unit, and a control unit that controls energization of the heating body based on the determination result stored in the storage unit.

  Preferably, the apparatus further includes removal means for removing the determination result stored in the storage means.

  Preferably, the determination means determines that there is an abnormality in energization of the heating body when the value of the temperature rise of the heating body is less than a set value and not more than a predetermined value.

  Preferably, the determination means determines that the heating body is abnormal when the value of the temperature rise of the heating body is less than a set value and greater than a predetermined value.

  Preferably, the determination means determines that the heating body is abnormal when the value of the temperature rise of the heating body is larger than a set value and larger than a predetermined value.

  Further, the third feature of the present invention is that a temperature rise of the heating body is detected before the temperature of the heating body heated by energization rises to a predetermined set temperature, and whether there is an abnormality based on the detection result. And a method for diagnosing a heating apparatus that outputs information based on the determination result.

  According to the present invention, an abnormality can be detected at the start of heating of the heating element.

Next, embodiments of the present invention will be described with reference to the drawings.
1 and 2 show an outline of an image forming apparatus 10 according to an embodiment of the present invention. The image forming apparatus 10 includes an image forming apparatus main body 12, an image forming unit 14 is mounted in the image forming apparatus main body 12, and a discharge unit 16 is provided on the upper portion of the image forming apparatus main body 12. For example, two-stage sheet feeding units 18 are disposed below the image forming apparatus main body 12.

  Each paper feed unit 18 has a paper feed cassette 20 and a paper feed roll 22 in which paper is stored, and the paper loaded in the paper feed cassette 20 is conveyed to the registration roll 24 by the rotation of the paper feed roll 22. Is done.

  Further, an image carrier 28 and a transfer device 36 of a process cartridge 46, which will be described later, are provided on the downstream side of the registration roll 24, and a fixing device 40 is further provided on the downstream side.

  Accordingly, the sheet fed from the sheet feeding cassette 20 of the sheet feeding unit 18 by the sheet feeding roll 22 is temporarily stopped by the registration roll 24 and passes between an image carrier 28 and a transfer device 36 described later at a timing. The developer image is transferred, and the transferred developer image is fixed by the fixing device 40 and discharged to the discharge unit 16 by the discharge roll 26.

  The image forming means 14 is of an electrophotographic system, and is charged by the image carrier 28 made of a photosensitive member, a charging device 30 made of, for example, a charging roll for uniformly charging the image carrier 28, and the charging device 30. An optical writing device 32 that writes a latent image on the image carrier 28 with light, a developing device 34 that visualizes with a developer containing a latent image of the image carrier 28 formed by the optical writing device 32, and this A transfer device 36 composed of, for example, a transfer roll for transferring the developer image by the developing device 34 to the paper, a cleaning device 38 for cleaning the developer remaining on the image carrier 28, and development on the paper transferred by the transfer device 36. It is composed of a fixing device 40 for fixing the agent image on the paper.

  The optical writing device 32 is composed of, for example, a scanning laser exposure device, and forms a latent image on the image carrier 28 across a process cartridge 46 described later. The cleaning device 38 includes a cleaning blade 43 that contacts the image carrier 32 and a developer recovery unit 44 that stores the developer scraped off by the cleaning blade 43.

  The process cartridge 46 is obtained by integrating the image carrier 28, the charging device 30, the developing device 34, and the cleaning device 38. For example, when the amount of the developer remaining in the developing device 34 is reduced, the process cartridge 46 is integrated. It can be exchanged.

  The fixing device 40 includes a heating roll 41 and a pressure roll 42 whose temperatures are controlled by a control device 56 described later, and fixes the developer image on the recording medium by heat and pressure.

The image forming apparatus 10 includes a display unit 50 such as an LCD panel, an input unit 51 such as a keyboard, a storage device 52 such as an HDD / CD device, a communication device 54, a control device 56, and the like. The control device 56 includes a CPU 57, a memory 58, and the like, and controls each part constituting the image forming apparatus 10.
In other words, the image forming apparatus 10 includes a function as a computer, and performs processing such as printing by executing a program received via the storage medium 59 or the communication device 54.

Next, a process in which the control device 56 controls the temperature of the heating roll 41 included in the fixing device 40 will be described in detail.
FIG. 3 is a configuration conceptual diagram showing the concept of the configuration for the control device 56 to control the temperature of the heating roll 41.
In FIG. 3, the same reference numerals are given to the substantially same parts as those constituting the image forming apparatus 10 shown in FIGS.

The heating roll 41 has, for example, a heating body 60 such as a heater inside. The heating body 60 has a rated output of 700 W, for example, and is heated by electric power (energization) supplied from the AC power supply 61 via the power supply path 62. In addition, the heating roll 41 is comprised by the member heated with the electric power supplied from AC power supply 61, and may not have a heater etc. inside.
The AC power supply 61 is configured to start or stop the supply of power of, for example, 100 V to the heating roll 41 according to the operation of the switch element 63 controlled by the control device 56.
The heating roll 41 is provided with a temperature sensor 64 that detects the temperature of the heating roll 41 (the temperature of the heating body 60). The temperature sensor 64 outputs the detected temperature to the control device 56.

  The control device 56 includes a temperature control unit 66 and a comparison / determination unit 68 configured by a program, for example. The temperature controller 66 receives the temperature detected by the temperature sensor 64 and operates the switch element 63 (on / off) so that the heating roll 41 reaches a predetermined set temperature (fixing temperature) for fixing the developer image on the recording medium. ) To control.

  The comparison determination unit 68 accepts at least two temperatures detected by the temperature sensor 64 with a predetermined time interval before the temperature of the heating roll 41 rises to a predetermined set temperature, and the temperature increase rate of the heating roll 41 S is calculated, and the state correspondence table 70 (see FIG. 4) provided in advance is compared with the calculation result to determine the state of the configuration for controlling the temperature of the heating roll 41, and the determination result is used as the temperature control unit. 66, output to the storage device 52 and the display unit 50. That is, the storage device 52 stores the result determined by the comparison determination unit 68 as a history.

FIG. 4 is a table showing an example of the state correspondence table 70 used by the comparison / determination unit 68 for determination.
The state correspondence table 70 classifies the state of the configuration for controlling the temperature of the heating roll 41 into, for example, four states according to the temperature increase rate S of the heating roll 41.

  For example, when the calculated temperature increase rate S is 3 ° C./second or less, the comparison / determination unit 68 compares the temperature increase rate S with the state correspondence table 70, and the power supply path 62 and the like are disconnected. (First state). Further, when the calculated temperature rise rate S is greater than 3 ° C./second and smaller than 10 ° C./second, the comparison / determination unit 68 compares the temperature rise rate S with the state correspondence table 70 and uses the 200V power supply. Is determined to be erroneously attached to the fixing device 40 (second state). In addition, when the calculated temperature increase rate S is 10 ° C./second or more and 13 ° C./second or less, the comparison determination unit 68 compares the temperature increase rate S with the state correspondence table 70 to perform heating. It is determined that the roll 41 is in a normal state (third state). In addition, when the calculated temperature increase rate S is greater than 13 ° C./s, the comparison / determination unit 68 compares the temperature increase rate S with the state correspondence table 70 to determine a heating roll with a rated output of 1000 W as a fixing device. 40 is determined to be erroneously attached (fourth state).

  Note that the determination result of the comparison determination unit 68 stored in the storage device 52 can be removed from a predetermined storage area such as being erased by the user via the input unit 51.

Next, processing for determining the state of the configuration for the control device 56 to control the temperature of the heating roll 41 will be described.
FIG. 5 is a flowchart showing a process (S10) for determining the state of the configuration for the controller 56 to control the temperature of the heating roll 41.
As shown in FIG. 5, in step 100 (S <b> 100), the control device 56 turns on the power supply (not shown) of the image forming apparatus 10 in accordance with a user operation input via the input unit 51. .

  In step 102 (S102), the control device 56 reads the determination result (information) of the comparison determination unit 68 stored in the storage device 52 from the storage device 52.

  In step 104 (S104), the control device 56 determines whether or not the information read in the processing of S102 includes abnormal temperature increase speed information (first, second, and fourth state history), and abnormal temperature increase. If there is speed information, the process proceeds to S128. If there is no abnormal temperature rise speed information (erased), the process proceeds to S106.

  In step 106 (S106), the temperature sensor 64 detects the initial temperature of the heating roll 41 (the temperature of the heating body 60) and outputs it to the control device 56.

  In step 108 (S108), the control device 56 turns on the switch element 63 (starts energization of the heating body 60).

  In step 110 (S110), the temperature sensor 64 detects the temperature of the heating roll 41 after a certain period of time (the temperature of the heating body 60) and outputs it to the control device 56.

  In step 112 (S112), the control device 56 calculates the value of the temperature rise rate S of the heating roll 41 and compares it with the state correspondence table 70.

  In step 114 (S114), the control device 56 determines whether or not the value of the temperature rise rate S of the heating roll 41 is 3 ° C./second or less, and if it is 3 ° C / second or less, S124. If it is not 3 ° C./second or less, the process proceeds to S116.

  In step 116 (S116), the controller 56 determines whether or not the value of the temperature rise rate S of the heating roll 41 is between 3 ° C./second and 10 ° C./second, and 3 ° C / second. If it is between the second and 10 ° C / second, the process proceeds to S124, and if not between 3 ° C / second and 10 ° C / second, the process proceeds to S118.

  In step 118 (S118), the controller 56 determines whether or not the value of the temperature rise rate S of the heating roll 41 is from 10 ° C / second to 13 ° C / second, and from 10 ° C / second. If it is up to 13 ° C / second, the process proceeds to S124, and if it is not from 10 ° C / second to 13 ° C / second, the process proceeds to S120.

  In step 120 (S120), the control device 56 controls the operation of the switch element 63 so that the heating roll 41 has a predetermined set temperature for fixing the developer image on the recording medium (fixing temperature control process).

  In step 122 (S122), the control device 56 stands by so that an image can be formed in response to the input of the image signal.

  In step 124 (S124), the control device 56 turns off the switch element 63 (stops energization of the heating body 60).

  In step 126 (S126), the control device 56 writes the result (information) determined in the processing of S114, S116, and S118 in the storage device 52.

  In step 128 (S128), the display unit 50 displays the abnormality by type (any of the first, second, and fourth states) according to the information stored in the storage device 52.

  As described above, the image forming apparatus 10 self-diagnoses the state of the configuration for controlling the temperature of the heating roll 41 before the heating roll 41 reaches a predetermined set temperature after the power is turned on.

1 is a cross-sectional view illustrating an outline of an image forming apparatus according to an embodiment of the present invention. 1 is a configuration diagram illustrating an overview of an image forming apparatus according to an embodiment of the present invention. It is a structure conceptual diagram which shows the concept of the structure for a control apparatus to control the temperature of a heating roll. It is a chart which shows the example of the state correspondence table which a comparison judgment part uses for judgment. It is a flowchart which shows the process (S10) which determines the state of the structure for a control apparatus to control the temperature of a heating roll.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image forming apparatus 12 Image forming apparatus main body 14 Image forming means 28 Image carrier 30 Charging device 32 Optical writing device 34 Developing device 36 Transfer device 38 Cleaning device 40 Fixing device 41 Heating roll 42 Pressure roll 46 Process cartridge 50 Display unit 51 Input unit 52 Storage device 54 Communication device 56 Control device 60 Heating body 61 AC power supply 62 Power supply path 63 Switch element 64 Temperature sensor 66 Temperature control unit 68 Comparison determination unit 70 Status correspondence table

Claims (15)

  Based on the result of detection by the detection means before the temperature of the heating body reaches a predetermined set temperature, the presence or absence of an abnormality is detected. A heating apparatus having a determination means for determining and an output means for outputting information based on the determination result of the determination means.   The heating device according to claim 1, wherein the determination unit determines the presence or absence of a plurality of types of abnormality based on a value of a temperature rise of the heating body.   The heating apparatus according to claim 1, further comprising a storage unit that stores a determination result of the determination unit, and a control unit that controls energization of the heating body based on the determination result stored in the storage unit.   The heating apparatus according to claim 3, further comprising a removing unit that removes the determination result stored in the storage unit.   The said determination means determines that there exists abnormality in the electricity supply to the said heating body, when the value of the temperature rise of the said heating body is less than a preset value and below a predetermined value. Heating device.   The heating device according to any one of claims 1 to 5, wherein the determination unit determines that there is an abnormality in the heating body when a value of a temperature rise of the heating body is less than a set value and greater than a predetermined value.   The heating device according to any one of claims 1 to 6, wherein the determination unit determines that there is an abnormality in the heating body when a value of a temperature rise of the heating body is larger than a set value and larger than a predetermined value.   A fixing device for fixing the developer image on the recording medium to the recording medium by a heating body heated by energization, a detecting means for detecting a temperature rise of the heating body, and before the temperature of the heating body reaches a predetermined set temperature. An image forming apparatus comprising: a determination unit that determines whether there is an abnormality based on a result detected by the detection unit; and an output unit that outputs information based on a determination result of the determination unit.   The image forming apparatus according to claim 8, wherein the determination unit determines the presence or absence of a plurality of types of abnormalities based on a value of a temperature rise of the heating body.   The image forming apparatus according to claim 8, further comprising: a storage unit that stores a determination result of the determination unit; and a control unit that controls energization of the heating body based on the determination result stored in the storage unit. .   The image forming apparatus according to claim 10, further comprising a removing unit that removes the determination result stored in the storage unit.   The said determination means determines that there exists abnormality in the electricity supply to the said heating body, when the value of the temperature rise of the said heating body is less than a preset value and below a predetermined value. Image forming apparatus.   13. The image forming apparatus according to claim 8, wherein the determination unit determines that the heating body is abnormal when a value of a temperature rise of the heating body is less than a predetermined value and greater than a predetermined value. .   The image forming apparatus according to claim 8, wherein the determination unit determines that the heating body is abnormal when a value of a temperature rise of the heating body is larger than a set value and larger than a predetermined value.   Before the temperature of the heating body heated by energization rises to a predetermined set temperature, the heating apparatus detects the temperature rise of the heating body, determines whether there is an abnormality based on the detection result, and outputs information based on the determination result Diagnosis method.

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