JPS63281183A - Fusing device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention is utilized in the technical field of fixing an unfixed image formed on a recording material with pressure between a pair of rollers in an electrophotographic apparatus, and in particular, The present invention relates to a fixing device including a device for preventing the recording material from being wrapped around the roller.

(Prior Art and Problems) As shown in FIG. 4 of the accompanying drawings, a conventional device of this type includes a fixing roller 1 having an internal heater (not shown) and a pressure roller 2. The recording material 5 having the unfixed image 4 was passed between the rollers 1 and 2 by the guide 3, and was heated and pressed to fix the image. In such an apparatus, there is a risk that the recording material 5 after fixing may wind around one of the rollers.

Separation claws IA and 2A with pointed ends were respectively abutted on both rollers 1 and 2 to prevent the above-mentioned wrapping.

However, because of the separating claws IA and 2A, the surfaces of both rollers 1 and 2 are easily damaged, which has an adverse effect on the image on the recording material when it is fixed, and an improvement has been desired.

(Means for Solving the Problems) The present invention solves the problems of the conventional apparatus as described above, and allows the recording material to be wound around the roller after 7 years without damaging the roller. An object of the present invention is to provide a fixing device that can prevent this.

In order to achieve the above object, the present invention includes a fixing roller that comes into contact with the surface of a recording material having an unfixed image on the unfixed image side, and a pressure roller that comes into pressure contact with the fixing roller, and a space between the two rollers. In the apparatus for fixing the unfixed image by passing the recording material, a peeling roller is disposed on the paper discharge side surface of the fixing roller and/or the pressure roller and contacts these rollers in the opposite direction. be done.

(Example) Hereinafter, the present invention will be described in detail based on FIGS. 1 to 3 of the accompanying drawings.

FIG. 1 is a sectional view showing an apparatus according to a first embodiment of the present invention.

In FIG. 1, the fixing roller l, pressure roller 2, guide 3, and recording material 5 with an unfixed image 4, which are given the same reference numerals as those in the conventional apparatus in FIG. 4, are the same, so they will be repeated here. Explanation will be omitted.

In the figure, the surface of the fixing roller l has a separating claw 6 similar to the conventional one.
are in light contact with each other due to the force of spring 7.

On the other hand, a peeling roller 8 that rotates in the same direction as the pressure roller 2 is disposed on the side of the pressure roller 2 . The peeling roller 8 is provided with, for example, four flexible fingers 81, 82.8:1.84 extending in the radial direction as shown in the figure. 81 is in pressure contact with the pressure roller 2 while being bent. Here, since the peeling roller 8 itself is rotating in the same direction as the pressure roller 2 as shown in the figure, when the flexible finger-like body 81 comes into contact with the pressure roller 2, the direction is opposite to the circumferential surface of the pressure roller 2. will be moved to.

Therefore, the recording material 5 that is trying to wrap around the pressure roller 2 is peeled off by the elastic restoring force of the flexible fingers 81 in the above-described bent state and sent upward.

A guide plate 9 is disposed directly above the peeling roller 8, and the recording paper 5 brought upward by the peeling roller 8 is guided by the lower surface of the guide plate 9.
The sheet is carried out by the flexible finger-like body 82 that comes to the position , and falls into the sheet discharge tray 10 disposed on the left and is stocked therein.

Note that the flexible fingers 81, 82, 83, 84 do not need to be provided continuously in the longitudinal direction of the pressure roller 2 (direction perpendicular to the plane of the paper), but may be formed at multiple locations at appropriate intervals. Good too. In that case, each flexible finger 1 can be arranged to pass within a groove 91 of said guide plate 9.

Next, a second embodiment of the present invention will be explained based on FIG.

In the previous example, the peeling roller was provided on the pressure roller side, but
Since the tendency of the recording material to wrap is not limited to the pressure roller side, in this embodiment, 8 stripping rollers are added to the pressure roller 2 side, and a similar stripping roller 8' is provided on the fixing roller L side. It is. This prevents the recording material from being wrapped around one roller. At this time, the recording material will be carried out between the flexible fingers of both peeling rollers, but in order to prevent the recording material from being damaged by being pinched by the flexible fingers of both rollers, Preferably, the phases of the flexible fingers are shifted.

Next, a third embodiment of the present invention will be described based on FIG. This embodiment is characterized in that the tip of the flexible finger-like body of the peeling roller 8 has an uneven portion 81A on the contact surface with the roller, making it easier to catch the tip of the recording material. Naturally, the flexible fingers having such a shape can be applied to both the peeling rollers on the pressure roller side and the fixing roller side.

(Effects of the Invention) As described above, the present invention is provided with a peeling roller that contacts the fixing roller and/or the pressure roller in the opposite direction to the paper discharge side of the fixing roller and/or the pressure roller, so that the recording material is not transferred to the roller. It is possible to eliminate damage to the roller while ensuring prevention of winding, thereby prolonging the life of the roller and improving fixing performance. Moreover, its structure is simple. Furthermore, if the contact portion of the peeling roller is formed into a soft, flexible finger-like body, the above effect is further improved.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an outline of a device according to a first embodiment of the present invention;
FIG. 2 is a cross-sectional view showing an overview of the device of the second embodiment, FIG. 3 is an enlarged cross-sectional view of main parts of the device of the third example, and FIG. 4 is a cross-sectional view showing an overview of a conventional fixing device. . １・・・・・・・・・・・・・・・Fixing roller 2
・・・・・・・・・・・・Second...Pressure roller 5...
・・・・・・・・・・・・・・・Recording material 8・・・・・・
・・・・・・・・・Peeling roller 81, 82, 83
．． 84...Flexible finger-like body 81A-...
...Concave and convex portion patent applicant Canon Co., Ltd. Agent Patent attorney Fujioka Temperature 3 Figure 4 Figure 1 Figure 2

Claims (3)

[Claims] (1) It has a fixing roller that comes into contact with the unfixed image side surface of the recording material having an unfixed image, and a pressure roller that comes into pressure contact with the fixing roller, and the recording material is passed between the two rollers and the unfixed image is fixed. A fixing device for fixing an image, characterized in that a peeling roller is disposed on the paper discharge side surface of the fixing roller and/or the pressure roller and contacts these rollers in the opposite direction. (2) Claim (1) characterized in that the peeling roller has a flexible finger-like body, and the flexible finger-like body is in elastic contact with the fixing roller and/or the pressure roller. Fixing device as described in section. (3) The fixing device according to claim (2), wherein the flexible finger-like body has an uneven portion on a contact surface with the fixing roller and/or the pressure roller.