JP3496913B2 - Fixing device control device and recording device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing device control device and a recording device. More specifically, the present invention relates to a fixing device control device that controls heating of a fixing device by a plurality of heating elements, and further to a recording device that has a fixing device that fixes the developer transferred onto a transfer member.

[0002]

2. Description of the Related Art In a recording apparatus equipped with a fixing device for fixing a developer onto a transfer sheet, the size of the sheet on which the fixing is carried out has been wide ranging from A5 to A3 in recent years.

For this reason, it becomes more necessary to control the temperature of the fixing device according to the paper size, and a fixing device having a plurality of heating elements or a fixing device in which the light distribution of each heating element is changed. Invented.

[0004]

However, when a plurality of heating elements having different performances (power consumption, light distribution, etc.) are mounted in the fixing device, heating control of the heating elements must be performed according to the performances of the heating elements. I have to. As a result, in order to prevent erroneous mounting, it is necessary to change the shape of each connector and provide an identification signal, which results in problems such as increased cost of parts, increased man-hours for assembly, and adjustment of inventory management. Cause

Therefore, an object of the present invention is to control the heating in accordance with the performance of the heating element and to control the temperature of the fixing device in accordance with the paper size, thereby preventing erroneous mounting and suppressing the manufacturing cost. An object of the present invention is to provide a fusing device control device that is capable.

Another object of the present invention is to incorporate a fixing device having the above-mentioned fixing device control device into a recording device and perform a fixing process according to the paper size, so that the developer can be evenly distributed on the paper. It is an object of the present invention to provide a recording apparatus that can fix an image efficiently and improve the reliability of image quality.

[0007]

The present invention includes first and second aspects.
Of the heating element, a constant voltage drive circuit that supplies a constant voltage to the heating element without depending on the input power supply voltage, and a temperature that detects the temperature of the fixing device heated by the first and second heating elements. After applying a voltage to the detection means and the first heating element without applying a voltage to the second heating element, the second heating element is applied.
Control means for controlling a voltage to be applied to the heating element; temperature detected by the temperature detecting means in a state where a voltage is applied to the first heating element without applying a voltage to the second heating element; The fixing device control device is provided with a judging means for judging the types of the first and second heating elements based on the temperature detected by the temperature detecting means in the state where the voltage is applied to the second heating element. Make up.

The first and second heating elements may have different light distributions or different power consumptions.

The fixing device control device may further include a temperature control unit that performs energization control based on the temperature detected by the temperature detection unit according to the determined type of the heating element.

The determination means may further detect the temperature detected by the temperature detection means in a state in which a voltage is applied to the first heating element without applying a voltage to the second heating element, and the second heat generation. Based on the temperature detected by the temperature detecting means in the state where a voltage is applied to the body, the first
And the abnormality of the second heating element may be determined.

The constant voltage drive circuit includes voltage detection means for detecting the voltage of the input power supply voltage, and drive control means for controlling the application time to the heating element per unit time according to the detected input voltage. May be included.

The determination unit determines the type of the heating element based on the time until the temperature detected by the temperature detection unit reaches a predetermined temperature or the temperature detected by the temperature detection element at a predetermined timing. May be. The determining means may determine that the heating element is abnormal when the temperature detected by the temperature detecting means is not within a preset range at a predetermined timing.

A recording device according to the present invention is a recording device having a fixing device for fixing the developer transferred onto a transfer member by a fixing device heated by a heating element, and the fixing device control device described above. The fixing device is characterized in that the fixing process is performed by using the fixing device whose heating is controlled by the fixing device control device.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in detail with reference to the drawings.

A first embodiment of the present invention will be described with reference to FIGS. 1 to 4.

FIG. 2 is a block diagram of an electric circuit in this example. 201 is a diode bridge that converts the AC power supply 201a into DC. 202 is a heater Ha,
It is a detection circuit of a voltage applied to Hb. Reference numeral 203 denotes a control circuit including a one-chip microcomputer that incorporates a ROM and a RAM for controlling the driving of the fixing heater.

In the control circuit 203, various means as will be described in detail with reference to a flow chart described later, that is, a predetermined delay time is set at the start of voltage application to the fixing device and voltage is applied to each heating element. Control means for controlling, performance judging means for judging the temperature rise degree after applying voltage to each heating element and judging the performance of the heating element, and heating by the heating element based on the judged performance of the heating element. Temperature control means for controlling the temperature of the fixing device, drive control means for controlling the application time to the heating element per unit time according to the detected input voltage, detected temperature increase rate and preset temperature increase reference Various means such as abnormality determining means for determining that the fixing device is abnormal when the values do not match are stored.

When the switching element Tr1 and the heater driving element Tr2 or Tr3 are turned on, a voltage is applied to the fixing heater. The voltage applied to the heaters Ha and Hb can be made constant by detecting and reading the applied voltage by the detection circuit 202 and changing the on-duty of the PWM signal applied to the gate of the switching element Tr1. Th is a thermistor that detects the temperature of the fixing roller heated by the heater.

FIG. 3 shows the structure of a heater which is a heating element. The heater Ha is a type 1 or type 2 heater. The heater Hb is a type 1 or type 2 heater. In this case, the type 1 heater is a heater having a peak of light distribution at both ends of the fixing roller 100 as a fixing device.
The type 2 heater is a heater having a light distribution peak at the center of the fixing roller 100.

FIG. 1 is a flow chart showing the control of the fixing heater in the present invention. FIG. 4 shows the temperature rise of the thermistor Th that detects the temperature of the surface of the fixing roller 100 when the same control is performed.

In this example, a description will be given of an example in which a plurality of heaters having different light distributions (heat generator performances) are used to perform heater discrimination control and drive control.

A type 2 heater having a light distribution peak at the center of the fixing roller 100 and a type 1 heater having a light distribution peak at both ends of the fixing roller 100 are connected to each other. Based on the control flow shown, heater driving signals FSRDA and FSRDB are output to the heater driving elements Tr2 and Tr3, and the thermistor Th is output.
Of the temperature of the heater drive elements Tr2, Tr
It is determined which type of heater is connected to each of the three.

First, the heater Ha connected to the heater driving element Tr2 is driven by the heater driving signal FSRDA (step S101), and the timer is started (step S102). Then, it waits until the temperature of the thermistor Th exceeds the temperature T1 (see FIG. 4) (step S10).
3) When the temperature is exceeded, the timer value is checked (step S104), and if it is within the time t1 to t2, the heater Ha connected to the heater driving element Tr2 is determined to be a type 1 heater ( Step S105). If it is not within the time t1 to t2, the timer value is checked (step S106). If it is within the time t3 to t4, the heater Ha connected to the heater driving element Tr2 is of type 2
The heater is determined to be the heater (step S107). If it is not within the time t3 to t4, it is determined that the heater Ha is neither type 1 nor type 2, and the driving of the heater Ha is stopped (step S117).

Further, the apparatus waits until the elapsed time from the start of driving the heater has passed the time t5 (see FIG. 4) (step S108), and at that time, starts driving the heater Hb connected to the heater driving element Tr3. Yes (step S1
09). The detected temperature of the thermistor Th is the temperature T
Wait until the number exceeds 2 (step S110). When the temperature is exceeded, the elapsed time at this time is time t6 to t7.
It is checked whether it is within (step S111). If it is within the time t6 to t7, it is checked whether the heater Ha is a type 1 heater (step S112). If it is type 1, the heater H connected to the heater driving element Tr3 is checked.
b is determined to be a type 2 heater (step S
114). If the heater Ha is not a type 1 heater,
The heater Hb connected to the heater driving element Tr3 is determined to be a type 1 heater (step S113).
In step S111, if it is outside the check time, it is determined that the heater Hb is neither type 1 nor type 2, a failure display is displayed on a display unit (not shown), and driving of the heaters Ha and Hb is stopped (step S111). S11
6). After that, the heaters Ha and Hb are all turned on until the fixing roller 100 reaches a predetermined standby temperature, and the temperature is controlled to be maintained until a print command comes.

In FIG. 4, X is an example showing the temperature rise when the heater Ha is a type 1 heater and the heater Hb is a type 2 heater. In X, since the heater near the thermistor Th is turned on first,
From the thermistor position, the rise in temperature rises quickly.

On the other hand, Y is an example showing the degree of temperature rise in the case where the heater Ha is a type 2 heater and the heater Hb is a type 1 heater. In Y, since the heater farther from the thermistor Th is turned on first, the rise of the temperature rises slowly when viewed from the position of the thermistor Th.

However, in any case, since the constant voltage is applied to the heater, the rate of temperature increase becomes the same after a fixed time.

When a print command is received, the lighting ratio of the heaters Ha and Hb is changed according to the size of the paper, and the optimum temperature control for the paper is performed. That is, in the case of the structure in which the temperature rise of X is shown in FIG.
And the heater Hb, which is a type 2 heater, is controlled at the same lighting ratio, and the heater Ha, which is a type 1 heater, and the heater Hb, which is a type 2 heater, are used for narrow paper such as A4 portrait paper. Is controlled so that the lighting ratio becomes Ha <Hb.

As described above, when the fixing device is started up, the heater is heated in a predetermined sequence to fix the fixing roller 1.
The performance of the heater (light distribution) is determined by where the temperature rises at 00, and the heating control is performed according to the performance of the determined heater. There is no need to drive in consideration of the procedure, and there is no need to use a different type of connector to prevent incorrect mounting. Further, this also eliminates the need for a procedure and confirmation for preventing erroneous mounting even in the assembly process of the fixing device.

Next, a second embodiment of the present invention will be described with reference to FIG.
And it demonstrates based on FIG.

FIG. 5 is a block diagram of an electric circuit in this example. In the above-described first embodiment, a plurality of heaters having different light distributions are used and the constant voltage output circuits Tr2 and Tr3 are used as heater driving circuits. However, in this example, the input voltage is detected by the input voltage detection circuit 501. The control circuit 203 controls the heater drive circuit 503 to change the on-time of the drive signals FSRDA and FSRDB so that the electric power per unit time applied to the heater in the control circuit 203 becomes constant according to the detected voltage. An example will be described in which two heaters of different types are used.

FIG. 6 shows how the temperature rises when a constant power is applied to each of the two heaters. Regarding the ratio of power consumption, it is assumed that the heater of type 1> the heater of type 2 is referred to with reference to the structure of FIG. 3 described above. In the case of the solid line V, the temperature rise rate is higher than that of the broken line W, so that the heater Ha =
It is determined that the heater is composed of the type 1 heater and the heater Hb = type 2 heater.

On the contrary, in W, it is determined that the heater Ha = type 2 heater and the heater Hb = type 1 heater. The control for making this determination is exactly the same as the flowchart shown in FIG. However, with the example of the first embodiment,
The times t1 to t7 are different from each other.

In this way, if the power applied to the heaters is constant, not only a plurality of heaters having different light distributions as in the example of the first embodiment but also the power consumption as in this example is consumed. Similar effects can be obtained even with a plurality of different heaters.

Next, a third embodiment of the present invention will be described with reference to FIG.
And it demonstrates based on FIG.

FIG. 7 is a flow chart showing the control of the heater. FIG. 8 shows the characteristics of the temperature rise change of the fixing roller when the heater is controlled.

In the example of the first embodiment described above, the validity of the time until the temperature reaches the predetermined temperature is checked in order to detect the temperature rise. However, in this example, the "temperature" after the predetermined time has passed. Check the validity of The heater control is
Since this is almost the same as the example of the first embodiment, only different parts will be described in this example.

In FIG. 7, waiting for a predetermined time t8 from the start of driving the heater Ha (step S70).
3), after the lapse of time t8, the temperature of the heater Ha is T5 to T6.
If within the range (step S704), the heater Ha =
The heater is determined to be a type 1 heater (step S105). If the temperature is not within the range of T5 to T6, the temperature is T3 to T4.
Check if it is within the range (step S706),
If within the range of T3 to T4, the heater Ha = type 2
The heater is determined to be the heater (step S107). If the type is neither type 1 nor type 2, the heater Ha is stopped and error processing is performed (step S117). The description of the control of the heater Hb is omitted.

As described above, the performance of the heater (types 1 and 2, light distribution distribution) is compared by comparing the temperature rise after the fixing roller 100 starts to rise in temperature with the preset reference temperatures T3 to T6. Power consumption) can be determined, and by this, it is possible to obtain the same operation as the example of the first embodiment.

The present invention may be applied to a system composed of a plurality of devices or an apparatus composed of a single device. Further, it goes without saying that the present invention can be applied to the case where it is achieved by supplying a program to a system or an apparatus. In this case, by reading a storage medium storing a program represented by software for achieving the present invention into the system or apparatus, the system or apparatus can enjoy the effects of the present invention.

[0041]

As described above, according to the present invention,
After the heater performance is detected, the heating control is performed according to the heater performance, so even if multiple heaters with different performances (light distribution, power consumption) are mounted on the fixing roller, the heater connection is required. There is no need to be aware of the position and procedure, and there is no need to use a different type of connector to prevent erroneous mounting. Further, in the assembling process of the fixing device, the procedure and the confirmation of the erroneous mounting prevention are unnecessary. Therefore, from the above, the component cost and the manufacturing cost in the assembly man-hour can be suppressed, and the inventory management can be easily adjusted.

Further, according to the present invention, the fixing device having the above-mentioned function is incorporated in the recording device, and when printing is performed on the recording paper, fixing is performed in accordance with the paper size, so that the paper is fixed on the paper. It is possible to fix the developer evenly and efficiently, and thus improve the reliability of image quality.

[Brief description of drawings]

FIG. 1 is a flowchart showing a heater discrimination control process according to a first embodiment of the present invention.

FIG. 2 is a circuit diagram showing a heater control circuit.

FIG. 3 is an explanatory diagram showing a configuration and a light distribution of a heater embedded in a fixing roller.

FIG. 4 is a characteristic diagram showing a temperature change on the surface of a fixing roller.

FIG. 5 is a circuit diagram showing a heater control circuit according to a second embodiment of the present invention.

FIG. 6 is a characteristic diagram showing a temperature change on the surface of a fixing roller.

FIG. 7 is a flow chart showing heater discrimination control processing according to a third embodiment of the present invention.

FIG. 8 is a characteristic diagram showing a temperature change on the surface of a fixing roller.

[Explanation of symbols]

100 fixing device 203 control means, performance determination means, temperature control means, drive control means, abnormality determination means 501 voltage detection means

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Junichi Kimizuka 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Norio Hashimoto 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Incorporated (72) Inventor Takayasu Yunochi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Hiroaki Sakai 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. ( 72) Inventor Yasunari Ohara 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (56) References JP-A-10-254288 (JP, A) JP-A-181832 (JP, A) ( 58) Fields investigated (Int.Cl. ⁷ , DB name) G03G 13/20 G03G 15/20

Claims (8)

(57) [Claims] 1. A first and a second heating element, and a heating element that generates a constant voltage independently of the input power supply voltage.
A constant voltage drive circuit for supplying to the first heating element, a temperature detecting means for detecting the temperature of the fixing device heated by the first and second heating elements, and the first heating element without applying a voltage to the second heating element. Control means for applying a voltage to the second heating element after applying a voltage to the heating element; and applying a voltage to the first heating element without applying a voltage to the second heating element. The type of the first and second heat generating elements is determined based on the temperature detected by the temperature detecting means in the above state and the temperature detected by the temperature detecting means in the state where a voltage is applied to the second heat generating element. A fixing device control device comprising: a determining unit; 2. The fixing device control apparatus according to claim 1, wherein the first and second heating elements have different light distributions or different power consumptions. Wherein the fuser control device further claim 1, characterized in that it comprises a temperature control means for performing in accordance with the type of the determined heating element, the current control based on the temperature detected by said temperature detecting means Alternatively, the fixing device control device according to claim 2. 4. The determination means is further configured to output the second call.
A voltage is applied to the first heating element without applying a voltage to the heating element.
Temperature detected by the temperature detecting means in the applied state
And the state where voltage is applied to the second heating element.
The first temperature based on the temperature detected by the temperature detecting means.
4. The fixing device control device according to claim 1, wherein an abnormality of the second heating element is determined . 5. The constant voltage drive circuit includes voltage detection means for detecting the voltage of an input power supply voltage, and drive control for controlling an application time to a heating element per unit time according to the detected input voltage. And means.
4. The fixing device control device according to any one of 3 to 3. 6. The determining means determines the type of the heating element based on the time until the temperature detected by the temperature detecting means reaches a predetermined temperature or the temperature detected by the temperature detecting element at a predetermined timing. The fixing device control device according to any one of claims 1 to 5, wherein: Wherein said determining means is not in the range that the temperature detected by said temperature detecting means is set in advance at a predetermined timing, to claim 4, characterized in that the heating element is determined to be abnormal The fixing device control device described. 8. The developer transferred onto a transfer member, a recording apparatus having a fixing device for fixing by the heated fuser by the heating element, the fixing device according to any one of claims 1 to 7 A recording apparatus comprising a control device, wherein a fixing process is performed by using the fixing device whose heating is controlled by the fixing device control device.