JPS5962884A - Image forming device - Google Patents

Abstract

PURPOSE:To make a light source only for illumination of an original unnecessary to reduce a required electric power and simplify the constitution by providing a means which uses a heating and light emitting member of a fixing device, which is provided with a transparent cylindrical member having the heating and light emitting member internally, as a light source for original exposure also. CONSTITUTION:A filter 30 is close to the circumferential face of a fixing roll 1 of a transparent cylinder and is arranged on a circle having the same center as the fixing roll 1 and is provided throughout in the axial direction of the roll 1. A specular surface reflective shade 9 covers this filter 30 and has a desired curved surface or the like to lead the light from a heating and light emitting member 3 to an original illuminating part A. A movable reflective shade 9a is provided on the illuminating part A side and is connected to the shade 9 by a turning supporting shaft 32 and is connected to a solenoid 21 and forms a desired aperture width together with the shade 9 to adjust the illumination exposure. A means 24 which controls the operation of the solenoid 21 moves the shade 9 on a basis of the signal from an exposure adjusting signal 22 to give a correct exposure. The means 24 prefers the control due to the adjusting signal 22 while an original exposure signal 23 is given, but the means 24 moves the reflective shade 9a to a position 9b to close the illumination aperture at the non-exposure time when this signal is not given.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrophotographic copying apparatus, and particularly to an image forming apparatus equipped with a novel fixing mechanism and original exposure light source mechanism.

Conventionally, this type of device was No. 1983-1979, USP3.
As seen in No. 911gll'1, there is a fixing roller that uses transparent heat-resistant glass as a fixing roller and has an infrared heating element inside it, but all of them have a heat generating element to heat and fix the unfixed toner image. It is not intended to be used as a light source for exposing originals.

The present invention provides an image forming apparatus which is equipped with a light emitting heating source to reduce the required generating power without providing a light 'KX' exclusively for document illumination, and to provide an image forming apparatus which is easy to construct, small in size and low in cost. With the goal.

In the present invention, the heat source of the fixing device that performs fixing is very high temperature by applying a constant pressure between two heated rollers and passing the unfixed toner image through the image support. The present invention was completed by paying attention to the fact that it emits light, and using it as a light source for exposing an original. Furthermore, in conventional image forming apparatuses that use heat roller fixing, more than half of the power consumption is used as a heat source for fixing, and about 20% to 30% is used as a light source for exposing documents. , the power consumption for document exposure according to the present invention is approximately 2-3
You can save money.

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

FIG. 1 is a side sectional view of the present invention. / is a fixing roller made of a transparent cylindrical cylinder made of heat-resistant glass or the like and a heat-emitting light-emitting member 3 such as a halogen lamp, and da is a heat-resistant elastic material such as silicone rubber or silicone sponge rubber. A pressure roller having the material S as the outer layer of the core A is brought into pressure contact with the fixing roller at least during fixing. The roller is a heat-resistant felt made of polyimide amide or the like impregnated with an anti-offset liquid such as silicone oil, which cleans the surface of the fixing roller and forms an anti-offset liquid layer on the surface of the fixing roller. g is a temperature detection member such as a thermistor for detecting the surface temperature of the fixing roller, and w is a temperature detection member such as a thermistor for detecting the surface temperature of the fixing roller. It is a specular reflective shade, and the width in the direction perpendicular to the plane of the paper in FIG. 1 is approximately equal to the width of the original platen glass.

Reference numeral 10 denotes a light-shielding shutter for preventing the source from the heat-generating light emitting member 3 from leaking toward the document platen glass except when exposing the original, and is located at the actual position when exposing the original, and at the position indicated by the broken line at other times. . The shutter io prevents the user from receiving direct light from the heat-generating light-emitting member 3 during waiting and standby for the copying operation of the image forming apparatus shown in FIG. The radiant heat is reflected back to the fixing device. Also ultraviolet m
A '11 jt&filter 30 is provided to prevent the temperature of the document table from rising and to use heat efficiently for fixing. Therefore, it is preferable that the filter 3θ has good heat reflectivity and large light transmittance.

When the main switch of the image forming apparatus shown in FIG. 1 is turned on, current flows through the heat generating light emitting member and the temperature of the fixing roller gradually rises. At this time, the light-shielding shutter/θ is at the dotted line position 10
It is in a. And at least when exposing the original, the heat generating light emitting member 3
When lit to start fixing, current continues to flow through the heat generating light emitting member 3 until the temperature of the fixing roller reaches the fixing temperature, and when the temperature reaches the fixing temperature or higher, the wait amplifier is completed and copying becomes possible. When copying starts here, the document glass platen// moves to the left once, and when it reaches the start position, the light-shielding shutter 10 comes to the position indicated by the solid line, and exposure of the original document on the document platen glass// starts. platen glass//
moves to the right. Here, charger/2, short focus lens 13 such as SELFOC lens array, bar lens, Sθ,
a photosensitive drum 19 having a layer of photosensitive material such as OdS on its outer periphery;
The powder developer on the developing roller/4' forms a developed image of the document on the document table glass 11 through a well-known process.

This developed image is conveyed via a paper feed roller 15 and a registration roller /6 and transferred to an image support material by a charger 7.7. After being transferred, the image support material is separated from the photosensitive drum /q by a known separation device (not shown). The image is transferred to the fixing device by the conveyor belt 1g, and is fixed under pressure by the fixing roller and the pressure roller.

The material of the transparent cylindrical cylinder of the fixing roller only needs to be heat resistant, and various materials can be used.In general, infrared-transparent quartz glass is most suitable, but Vycor and Pyrex (products Furthermore, it is more desirable to provide a transparent heat-resistant and releasable outer layer such as Teflon on the outer layer of the transparent cylindrical cylinder 2, since this prevents the fixing roller 1 from becoming dirty.

Another embodiment of the invention is shown in FIG. The filter 3θ in FIG. 2 is a transparent cylinder that is close to the circumferential surface of the fixing roller/, is arranged in a concentric relationship with the fixing roller/, and covers a part of the cylinder provided in the entire axial direction of the fixing roller/. It is a curved plate made of eggplant.

This filter? θ covers almost the entire circumference of the fixing roller l except for the pressure contact portion with the pressure roller.

The flit-resistant felt 7 and the temperature sensing member g are provided inside this filter 30. This eliminates wasteful heat release and enables appropriate temperature control.

The felt 7 stabilizes the light supply in order to accurately clean the surface of the fixing roller 1.

The specular reflection shade 9 has a desired curved surface for covering the filter 30 and guiding the light from the heat generating light emitting member 3 to the document illumination section A. The reflective shade t also serves as an upper guide plate at the entrance of the image support material to the fixing device, and supports the separation claw 3/ together with the filter 30 at the discharge section of the fixing device. On the other hand, there is a movable reflective shade 9 on the illumination part A side of the reflective shade 9.
A is provided, and the main body of the reflective shade and the rotation support shaft 3
．． It is connected by 2. The movable reflective shade qa is connected to a solenoid λ/, and a desired opening width is formed with the reflective shade by the solenoid 2/, so that the amount of illumination exposure can be adjusted.

λhiro is a means of controlling the operation of a solenoid.

When exposure amount adjustment No. 2.2 is received through known electrical or mechanical processing, the reflective shade qa is moved to provide an appropriate exposure amount. Further, the control means 21I is also given a document exposure signal 23, and while this signal 23 is given, the control by the adjustment signal 22 is given priority, and when this signal is not given, that is, during non-exposure, the control by the adjustment signal 22 is given priority. The reflective shade 9a is moved to the position '7b' and the illumination aperture is closed. Needless to say, when the thermal exposure signal 23 is applied, the reflective shade 9a is moved to form an illumination aperture.

With this configuration, it is possible to correct the exposure amount and also to prevent the light from being emitted from the light emitting member in vain. Further, if the members are used in common, the number of parts is reduced, and the device can be made more compact. Note that ZS is a guide for the transfer material. Furthermore, the filter 30 provides a stable fixing effect. Incidentally, the light emitting section 3 is controlled by known means so as to turn on the document illumination center.

, for example, temperature control flrl between the temperature detection cord g and the light emitting member 3
The J control means 26 has an ordinary temperature control circuit (known in the art) λ and a current supply means λg, and has a switching means 27 for selectively utilizing these. Usually means 27
is connected to the temperature control circuit 29, but the dew C signal 23
When it is transmitted, the means, 27 is the circuit, 2? energizing means,
2g, and the light emitting member is turned on during exposure. Furthermore, when this signal 23 is cut off, the means 27 is activated by the energizing means]g
The circuit is then switched to circuit 2q and normal temperature control is performed. Anything based on this idea can be applied to the present invention.

In the explanation of FIG. 2, it is assumed that the movable reflector qa is driven by a solenoid, 2/, but the movable reflector qa is driven by the movable reflector 9.
For example, a pulse motor or the like may be used as a drive source and driven via 'Dti9 so that positioning can be performed continuously.

As described above, the present invention provides a fixing device comprising a transparent cylindrical member having a heat-generating light emitting member on the inner side 15 and a suppression roller covered with an elastic body in contact with the cylindrical member. In order to use the heat generating light emitting member inside the transparent cylindrical member as a light source for exposing the original, an optical path is provided between the fixing device and the original platen glass. Since the power source is used as a light source, the image forming apparatus requires only 10 Ng of power and energy, which further reduces power consumption, making it possible to provide a compact and low-cost image forming apparatus. Ta. Since the fixing roller is covered with a filter, the amount of heating by the heater is reduced, and since it has good translucency, it can be fully utilized for illuminating raw materials, resulting in energy savings. The optical path from the heater to the manuscript interview is reflected with a reflective shade.
Since the light is covered, the light can effectively reach the original, and since the reflective shade is movable in the original irradiation section and the opening area can be adjusted, appropriate exposure illumination can be obtained.

[Brief explanation of drawings]

FIG. 1 and FIG. 2 are the fruits of the present invention, I+Iiii I,
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Claims (1)

[Claims] / An image thickness device comprising: a fixing device having a transparent cylindrical member having a heat-generating light-emitting member therein; and means for using the heat-generating light-emitting member within the transparent cylindrical member as a light source for exposing an original.