JPH08160794A - Heat roller type fixing device - Google Patents

Abstract

PURPOSE: To raise the temp. of a heat roller in a short time, by heating a fix- heat-pressing part area of the heat roller from the inside with use of a heat reaction plate, and limiting a heating range to one part of the area, as to the heater in the heating roller. CONSTITUTION: At the time of fixing the toner, the heater lamp 13 in the heat roller 10 heats the fix-heat-pressing part area of the heat roller 10 with the heat ray reflection plate 12, in other words about a half area before the fix-heat- pressing part 58 in the rotary direction is heated from the inside, thus the heating range is limited in a part of the area, therefore the temp. of the heat roller 10 is raised in a short time. On the other hand, the recording paper P with the toner image transferred by the unfixed toner M by the transfer device disposed on the upstream side of the fixing device is transported between the heating roller 10 and the pressure roller 53, and pressed to the heating roller 10 side by the pressure roller 53, and then the resin of the unfixed toner M is melted by the heat of heat roller 10, and thus the toner image is transferred.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing device used in an electrophotographic recording apparatus, and more particularly to a heat roller type toner fixing device using a heat roller.

[0002]

2. Description of the Related Art FIG. 5 shows a conventional example. The heat roller type toner fixing device is incorporated as a part of the printing device, and is arranged downstream of the toner image transfer device (not shown) in the conveyance path of the recording paper P. This heat roller type toner fixing device includes a heating roller 50 having a heater therein,
A part of the heating roller 50 is arranged in parallel with the heating roller 50,
The pressure roller 53 has an outer peripheral surface formed of an elastic member.

In order to enhance the heat storage effect, the heating roller 50 has a storage heat heating roller member 51 which is a thick aluminum cylinder having a large heat capacity. The storage heat heating roller member 51 has fluorine on its outer surface. It has a resin coating layer and has a black treatment layer on its inner surface, which has a great heat storage effect. The storage heat heating roller member 51 is rotatably locked inside the casing of the printing apparatus, and is given a rotational force by a drive mechanism (not shown).

Further, the heating roller 50 has a heater lamp 52, such as a halogen lamp or a xenon lamp, which is fixed inside the casing so as not to rotate, as a heat source, at the center of the hollow inside of the storage heat heating roller member 51. The storage heat heating roller member 51 has the black processing layer on the inner surface irradiated with infrared rays while being heated, and is uniformly heated.

The printing operation is performed after the controller (not shown) recognizes that the surface temperature of the storage heat heating roller member 51 detected by the temperature sensor 57 has risen to a predetermined temperature. After the unfixed toner M is transferred onto the recording surface of the recording paper P by the transfer device located on the upstream side of the heat roller type rotary fixing device, the heating roller 50 and the pressure roller 53.
The recording surface is conveyed to the abutting portion (fixing heating / pressurizing portion 58) with the recording surface facing the heating roller 50 side.
Pass 8. At this time, the resin contained in the unfixed toner M on the recording paper P is melted by the heat of the heating roller 50, further pressed by the pressure roller 53, and fixed on the recording paper P. At this time, the storage heat heating roller member 51 is measured by the above-mentioned temperature sensor 57 so that heat is not taken by the recording paper P and the pressure roller 53, and the temperature does not drop below a predetermined temperature due to heat radiation from the outer peripheral surface. Based on temperature, the controller
The heat lamp 52 is controlled so as to maintain a predetermined temperature.

When the unfixed toner M is fixed, the recording paper P is transferred to the heat storage heating roller member 51 by the peeling blade 54.
The toner that has been peeled off from the heat storage heating roller member 51 and adhered to the outer peripheral surface of the heat storage heating roller member 51 is scraped off by the cleaner blade 55 disposed with its tip facing the heat storage heating roller member 51, and then wiped by the cleaner filter 56. Taken.

[0007]

As described above, the heat roller type fixing device of this type includes the heat storage heating roller member 5.
Since the heat capacity of 1 is large, it is necessary to preheat the heat storage heating roller member 51 to a predetermined temperature before the printing operation is performed. The temperature characteristic of the heating roller 50 at this time is that the temperature rise from room temperature is 3.6 [° C / revolution] as shown in Fig. 6, and it is necessary to reach a predetermined temperature (180 to 200 [° C]). The heat storage heating roller member 51 needs to rotate about 50 times,
This causes a waiting time of about 1 to 3 minutes from the traveling speed of the recording paper P.

As described above, since the conventional heat roller type fixing device takes a long time to preheat, in order to keep the printing device ready for use, the heater lamp 52 maintains the preheating even when the recording paper P is not fixed. It is necessary to keep applying electric power, and it is necessary to continuously idle the heat storage heating roller member 51 in order to avoid deformation of the heat storage heating roller member 51 due to high temperature. It was an obstacle to power saving.

[0009]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a heat roller type toner fixing device which shortens the preheating time of the heating roller of the conventional example and is suitable for power saving.

[0010]

SUMMARY OF THE INVENTION The present invention comprises a heating roller equipped with a heater therein and a pressure roller equipped corresponding to the heating roller. In addition to the structure that pressurizes and fixes the recording paper with the unfixed toner sent to the, the heat roller is equipped with a heat ray reflection plate, and this heat ray reflection plate allows infrared rays emitted from the heater to be unfixed toner. It is characterized in that it is equipped so as to irradiate toward the fixing heating / pressurizing portion region on the inner surface of the heating roller on the side in contact with the attached recording paper.

Here, the direction of irradiation of infrared rays by the heat ray reflecting plate is, in particular, in the fixing heating / pressurizing area, before the rotation side on the side where the recording paper with unfixed toner is fed inside the heating roller. Therefore, the irradiation may be limited to the 1/4 part.

In addition to the above-mentioned structure, a temperature sensor provided along with the heating roller and a heating control circuit section for controlling the temperature of the heater to a predetermined temperature by the output of this temperature sensor are added.
In this heating control circuit section, the heater performs heating control so that the temperature of the fixing heating / pressurizing section can reach a predetermined temperature necessary for fixing the toner while the rotation of the heat roller is 1/2 to 1/4 rotation. It may be configured to have means. Here, the predetermined temperature refers to a temperature at which fixing is possible.

[0013]

The heater in the heating roller heats the fixing heating / pressurizing portion area of the heating roller from the inside by the heat ray reflection plate, and the heating range is concentrated in a part of the area, so that the heating roller rises in a short time. Warm.

Further, a temperature sensor is provided side by side with the heating roller,
When the heater has a heating control circuit that controls the temperature of the heater to a predetermined temperature based on the output of the temperature sensor, the heating controller appropriately heats the heater based on the temperature of the heating roller detected by the temperature sensor. By doing so, the temperature of the heat roller rises to a predetermined temperature while the heat roller rotates ½ to ¼ during driving.

[0015]

Embodiments of the present invention will be described below with reference to FIGS.
Shown in The present embodiment is incorporated as a part of an electrophotographic recording apparatus, and fixes unfixed toner M on recording paper P on the downstream side of a toner image transfer device (not shown) in the conveyance path of recording paper P. It is provided as a fixing device.

FIG. 1 shows this embodiment. In the present embodiment, the heating roller 10 equipped with a heater inside, the pressure roller 53 equipped corresponding to the heating roller 10, the heat ray reflecting plate 12 disposed inside the heating roller 10, and the heating The temperature sensor 57 provided side by side with the roller 10 constitutes the main part, and the heating control circuit section described later allows the heating roller 1
0 temperature control is performed.

The heating roller 10 is a roller main body 11 which is a thin-walled cylindrical member rotatably supported inside the casing of the printing apparatus, and the inside of the casing of the printing apparatus which is disposed inside the roller main body 11. And a heater lamp 13 that functions as a heater.

The roller body 11 is made of an alloy having good heat conductivity such as aluminum and titanium and has a diameter of 30 to 45 m.
m, the length is longer than the width of the recording paper P and the thickness is 0.5 to 1 mm, and it is a tubular member having a fluororesin coating layer on the outer surface and a black treatment layer on the inner surface. A gear mechanism (not shown) is provided at one end of the roller body 11 in the axial direction, and a rotational force is applied from a drive source (not shown) via the gear mechanism so as to be at the same speed as the conveyance speed of the recording paper P. Drive with.

The heater lamp 13 uses a halogen lamp, a xenon lamp, or the like, and is arranged inside the roller body 11 near the area of about 1/2 of the rotation before the recording paper P is fed. Furthermore, in the roller body 11,
The heat ray reflection plate 12 is fixedly supported inside the casing similarly to the heater lamp 13. The heat ray reflection plate 12 is made of stainless steel plate having a thickness of 0.3 to 0.5 mm and is radiated from the heater lamp 13. Infrared rays are arranged so as to reflect the infrared rays from the fixing heating / pressurizing section 58 on the inner surface of the roller body 11 to about a half before the rotation.

The other structure is the same as that of the conventional example, and the same reference numerals are used to omit the duplicated description.

When fixing the toner, the heating roller 1 is used.
The heater lamp 13 in 0 heats the fixing heating / pressurizing portion area of the heating roller 10 by the heat ray reflection plate 12, that is, the area about 1/2 before the rotation of the fixing heating / pressurizing portion 58 from the inside, so that the heating range is increased. Since it is concentrated in a part of the area, the temperature of the heating roller 10 rises in a short time. On the other hand, recording paper P
The toner image formed by the unfixed toner M is transferred by the transfer device disposed on the upstream side of the fixing device, and the toner image is conveyed between the heating roller 10 and the pressure roller 53.
3 is pressed against the heating roller 10 side, and the unfixed toner M
The resin is melted by the heat of the heating roller 10, and the toner image is transferred.

FIG. 2 shows the temperature characteristic of the heating roller. According to this, when the roller body 11 rotates, the fixing heating / pressurizing unit 58
The temperature rises abruptly in about 1/2 part before the rotation. The temperature is raised until it reaches the fixing heating / pressurizing unit 58, the heat is taken away by the recording paper P and the pressing roller 53 in the fixing heating / pressurizing unit 58, and the temperature is lowered, and it is an unirradiated area of the heater lamp 13. Since the heat is not supplied in the approximately 1/2 rotation portion, the temperature further decreases slightly, and the heating is performed again in the heating area.

Here, the maximum temperature rise is set to 216 [° C./revolution] in consideration of the recording speed of the electrophotographic recording apparatus and the start-up time of the heater lamp 13, and the predetermined temperature is maintained while the roller body 11 rotates about three times. Is reachable. From the running speed of the recording paper P, a predetermined temperature of 180 to 200 [° C]
It takes about 3 to 10 seconds to reach, so no waiting time for preheating is required. Here, if the maximum temperature rise is set to 360 [° C./revolution] or more, it will take a shorter time, for example, 1/2 to 1/4 of the rotation of the heating roller 10.
A predetermined temperature can be reached by rotation.

The heating control circuit section 20 will be described with reference to FIG. The heating control circuit unit 20 includes a temperature sensor 5
The heater lamp 13 is controlled to a predetermined temperature on the basis of the output of the CPU 7, and is composed of a CPU 21, a ROM 22 storing a storage program, a RAM 23, and a switch controller 24.

The temperature sensor 57 detects the temperature at a position 90 [deg.] Before the rotation with respect to the fixing heating / pressurizing unit 58 on the outer peripheral surface of the roller body 11, and the detected temperature is used as a signal for the A / D converter. It is transmitted to the heating control circuit section 20 via 25. The power supply 26 is controlled by the switch controller 24 to apply power to the heater lamp 13.
The power supply 26 has a small-capacity secondary battery 26a for applying overpower that accelerates the heating start-up that exceeds the rating of the heater lamp 13, and the secondary battery 26a discharges for heating. Has secured the power of.

Based on FIG. 4, the heating control circuit section 2 described above is used.
A method of controlling the heating roller 10 by 0 will be described. First,
The temperature sensor 57 detects the surface temperature of the fixing heating / pressurizing unit 58 of the roller body 11 at 90 degrees before the rotation (step S1). When the detected temperature is transmitted, the heating control circuit unit 20 determines whether the temperature difference T between the detected temperature and the predetermined fixing temperature is larger than 50 [° C.] (step S2). When the temperature difference T is larger than 50 [° C.], the power supply 26
The acceleration overpower is applied to the heater lamp 13 by the secondary power source 26a (step S3). As a result, the heating roller 10 is heated at a rate of increase exceeding 216 [° C./revolution]. The operations from steps S1 to S3 are repeated until the temperature difference T becomes 50 [° C.] or less.

On the other hand, when the temperature difference T is smaller than 50 [° C.], the secondary battery 26a is not used and a certain ratio of electric power, that is, [100 − ((50−T) /0.5)] [ %] And the heater lamp 13 is applied (step S4). Then, the temperature at the fixing heating / pressurizing unit 58 is predicted from the temperature at the measurement location of the temperature sensor 57. That is, the heating roller 10 raises the temperature at 216 [° C./1 rotation] when the maximum power is supplied to the heat lamp 13, and the temperature sensor 57 rotates 90 degrees before the fixing heating / pressurizing unit 58 (1 degree) (1
/ 4 rotation), there is a temperature difference of about 50 [° C.] from the temperature sensor position, and a value obtained by multiplying this by the above-mentioned ratio is [(216/4) × (100 − ((50− T)
/0.5))] [° C] is expected to be higher than the detected temperature. It is judged whether or not the predicted temperature reaches a predetermined temperature with an error of 5% in the upper and lower directions (step S5). If the predicted temperature is the predetermined temperature, power is continuously applied in that state (step S).
6). If the predicted temperature deviates from the predetermined temperature, the heating roller 10 is corrected based on the empirical data so as not to overshoot or undershoot (step S7).

As described above, in this embodiment, the temperature of the heating roller immediately rises, so that the preheating time is shortened and the waiting time associated therewith is greatly shortened. In addition, power consumption is reduced because power consumption for raising the temperature is reduced.

Here, in the above embodiment, by providing the temperature sensors at two or more places and appropriately arranging them, the temperature detection can be performed with higher accuracy. Further, in this embodiment, since the secondary battery is provided, it is possible to perform heating that exceeds normal heating. Since this secondary battery is an auxiliary battery, it may be removed from the configuration if the temperature of the heating roller rises within a sufficiently short time with only an ordinary power supply source.

Further, since the heat roller type fixing device shown in this embodiment has an extremely short preheating time, when it is used by being incorporated in an electrophotographic recording device or the like, the heat lamp power source of the heating roller is turned on during the standby of the fixing operation. It can be cut off. Further, a recording paper sensor may be provided on the upstream side of the recording paper conveyance path, so that when the recording paper is conveyed to the vicinity of the fixing device, the heat roller is powered on and a preheating operation is performed. As a result, it becomes possible to further save power.

[0031]

According to the present invention, the heater is provided inside the heating roller and the infrared rays emitted from the heater are radiated to the fixing heating / pressurizing region on the inner surface of the heating roller. The temperature of the heating roller rises faster than that of the one used, and the time required to reach the predetermined temperature for fixing can be greatly shortened, and since the temperature rises in a short time, the heating roller is always in a steady heating state. Since it is not necessary to keep it, power consumption due to heating is reduced,
It is possible to provide a heat roller type toner fixing device which is excellent in power saving and has never been provided.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a temperature rising state according to an embodiment of the present invention.

FIG. 3 is a configuration diagram of a heating control circuit unit according to an embodiment of the present invention.

FIG. 4 is an operation explanatory diagram of the embodiment of the present invention.

FIG. 5 is a schematic explanatory view showing a conventional example.

FIG. 6 is an explanatory diagram showing a temperature rising state of a conventional example.

[Explanation of symbols]

 10 Heating Roller 11 Roller Main Body 12 Heat Ray Reflector 13 Heater Lamp (Heater) 20 Heating Control Circuit Section 53 Pressure Roller 57 Temperature Sensor 58 Fixing Heat Pressing Section M Unfixed Toner P Recording Paper

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location H05B 3/10 B 0380-3K

Claims (3)

[Claims] 1. A heating roller equipped with a heater therein,
A pressure roller provided corresponding to the heating roller is provided, and the recording sheet with the unfixed toner fed between the pressure roller and the heating roller is heated and pressure-fixed. In a heat roller type toner fixing device, a heat ray reflecting plate is provided in the heating roller, and the heat ray reflecting plate is provided on the side where the infrared rays emitted from the heater come into contact with the recording paper on which the unfixed toner is attached. A heat roller type toner fixing device, characterized in that it is equipped so as to irradiate toward a fixing heating / pressurizing portion area on the inner surface. 2. The irradiation direction of infrared rays by the heat ray reflection plate is such that a half to a quarter of the front side of the rotation of the inside of the heating roller on which the recording paper with unfixed toner is fed is irradiated. 2. The heat roller type toner fixing device according to claim 1, wherein the heat roller type toner fixing device is set. 3. The heat roller type toner fixing device according to claim 1, further comprising a temperature sensor provided side by side with the heating roller, and a heating control circuit section for controlling the temperature of the heater to a predetermined temperature by the output of the temperature sensor. The heating control circuit unit is configured to raise the temperature of the fixing heating / pressurizing unit to a predetermined temperature necessary for fixing the toner by ½ to ¼ rotation of the rotation of the heating roller. A heat roller type toner fixing device comprising means for controlling heating of the toner.