JPS6170571A - Image forming device - Google Patents

Abstract

PURPOSE:To attain good fixability in white-and-black recording as well as color recording by changing the fixing temperature in a heat fixing device in accordance with the color of image forming materials. CONSTITUTION:When a push button switch 7 for color copy is turned on, a control pat 6 sets the temperature of a heat roll 1 to a higher value. For example, the control pat 6 sets the fixing temperature to 190 deg.C (the temperature most suitable for fixing of a color toner) when the switch 7 is depressed, but the control part 6 sets the fixing temperature to 180 deg.C (the temperature most suitable for fixing of a black toner) when the switch 7 is not depressed. In this roll fixing device, the fixing temperature is set to 180 deg.C in case of white- and-black copy and is set to 190 deg.C by depression of the switch 7 in case of color copy. Thus, a good fixability is attained in case of white-and-black copy as well as color copy.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an image forming apparatus equipped with a heat fixed tube device n for thermally fixing an image forming material onto a recording medium.

(Prior art) In image forming apparatuses such as electronic copying systems and laser printers, images are formed on C11 recording media such as paper or film using image forming materials such as 1-toner, Heat setting 1i is carried out using a heat setting UVTM such as a heat flash method or a heat flash method.

<Problems to be Solved by the Invention> Incidentally, the degree of heat absorption of this image forming material differs depending on its color, but the conventional apparatus does not take this point into consideration. For example, in the case of reproduction, even though B color toner has poorer C heat absorption than black toner, the fixing temperature (set temperature) in the heat fixing device is selected to be the same as that of black toner. There was a problem that the selection of cases was insufficient.

The present invention has been made in view of these points, and its purpose is to provide black-and-white and color li+T I't jib!
! , the image forming device that can obtain good definition even if there is a problem is 1♀(1(b).

(Means for solving the problem) The present invention solves the above problem,
An image with heat fixing '1AY (~1 formation device, fixed '4'I) in the heat fixing device;
uAl,! J is changed depending on the color of the image forming material 1
! 7 Things I tried to do 1! f12.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

Figure 1 is one of the fruits of the present invention! FIG. 3 is a configuration diagram of main parts of an example.

This embodiment relates to a copying machine using a roller fixing device as a heat fixing device, and only the configuration of the roller fixing device portion is shown, and other configurations are omitted because they are the same as conventional copying machines. In the figure, reference numeral 1 denotes a heating roller made of a metal cylinder, the surface of which is covered with a non-adhesive material (such as heat-resistant rubber) to which toner does not adhere. Inside this heating roller,
The heating element 2 such as a heating lamp is 1iil! Also, a 4 degree detection element 3 for detecting the temperature of the heating roller is arranged opposite to the outer peripheral surface of the heating roller. Reference numeral 4 denotes a pressure bonding loaf made of silicone rubber.While the heating roller contacts the surface of the transfer paper P on the toner image C side, this pressure roller 4 contacts the surface opposite to the toner image C side, and the roller shaft 5
rotated by ,, 6 is a control unit that controls the temperature of the heating roller 1. Normally, it also controls the copying sequence, but here it controls the temperature of the heating roller 1. Only the signal line for controlling the temperature of the roller 1 is shown.

The copying machine of this embodiment uses color toner (yellow).

Equipped with a phenomenon device (Mazenk, Cyan, etc.)? If you use it, you can make color copies, and if you install a black toner phenomenon device, you can make black and white copies.
Can do 7. Reference numeral 7 in the figure is a switch that informs the control unit 6 whether to perform a can copy or a black and white copy, and is provided, for example, on the operation unit (operation panel). This is a push button switch for color copying.

When this switch f-7 is turned on, the control section 6 heats and sets the temperature of the 1-ra 1 to be high. For example, when the switch 7 is pressed, the control unit 6 lowers the fixing temperature to 190.
℃ (optimum temperature for fixing color toner) ( ), and when switch 7 is not pressed, set to 180 ℃ (optimum temperature for fixing black toner). Note that the rollers 1 and 4 are configured to rotate while maintaining a constant pressure contact state in a pressure machine groove (not shown). In such a roller fixing device, the transfer paper P is sandwiched between the heating roller 1 and the pressure roller 4, and is transferred in the direction of the arrow while receiving heat from the heating roller 1.
J, and due to heating during movement, toner image C is transferred to transfer paper F]
be fused to.

According to the above configuration, the fixing temperature is set to 180° C. when black-and-white copying is performed, and is set to 190° C. when the switch 7 is pressed when color copying is performed. Therefore,
For any number of black-and-white and color cards, a good constant property is obtained (
You can get rid of it.

Incidentally, if black and white or color copying is to be performed by replacing the developing device, as shown in FIG. The microswitch 9 may be turned on to detect which phenomenon device is currently attached. In this way, it is possible to automatically change the fixing temperature. Of course, there are other methods for automatically changing the fixing temperature. for example,
A bar code or other code is attached to the developing device, and this is read optically or the color of the toner inside the developing device or on the photosensitive drum is detected, and this machine identifies which developing device is installed. Also, in the case of manual setting, the switch 7 of the above embodiment can be placed inside the front door of the Fukko Tatsumi. You may also use other types of switches.

Furthermore, in terms of copy volume, there are so-called color copying machines that have four built-in developing devices containing yellow, magenta, cyan, and black toners; The idea of the present invention of changing the temperature can be applied.

Further, the present invention can be applied to image forming apparatuses other than copying machines.

(Effect of Q Light) As explained above, according to the present invention, it is possible to select a fixing temperature suitable for the color of the image forming material, so that good fixing performance can be improved by 1W. Furthermore, since the fixing temperature is not increased unnecessarily, the durability of the fixing device and abnormal deformation of the recording medium can be avoided.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of the main parts of an embodiment (copy; shallow) of the present invention,
FIG. 2 is a diagram showing the main part of another embodiment of the present invention. 1... Heating roller 2... Heating element 3... Warm 1
Detection cord 4...Crimping [1-RA 6...Small II
G11 section 7...Switch 8...JT,!
I (+Device 9...Microphone 1:] Switch Applicant Roku Konishi Photography Anlin Shikikai γ [Agent
Patent attorney F #, T island suspension, 1 extraterritorial person

Claims (1)

[Claims] An image forming apparatus equipped with a thermal fixing device for thermally fixing an image forming material onto a recording medium, characterized in that the fixing temperature in the thermal fixing device can be changed depending on the color of the image forming material. Forming device.