JPH0547966U - Fixing device - Google Patents

Abstract

(57) [Summary] [Purpose] The purpose is to peel transfer paper that is in close contact with a fixing roller or a pressure roller with less impact. [Structure] A plurality of peeling claws 4 are arranged with respect to the fixing roller 1 or the pressure roller 2 so as to be sequentially delayed in the radial direction with reference to a part of the roller in the axial direction.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a fixing device such as a copying machine.

[0002]

[Prior Art]

 In a copying machine or the like, the transfer paper carrying an unfixed toner image is sent to a heat fixing device, where it is fused and fixed on the transfer paper. A roller type fixing device is known as one of the most popular heat fixing devices. The roller type fixing device is composed of a heating roller heated by a heater and a pressure roller or belt pressed against the heating roller, and carries an unfixed toner image between the heating roller and the pressure roller (or belt). The toner image is fixed by passing through the transfer sheet. Since the transfer paper comes into close contact with the heating roller during this passage, one or more peeling claws are arranged so as to contact the peripheral surface of the roller to forcibly peel the transfer paper from the roller surface. Conventionally, a plurality of peeling claws are arranged in parallel in the axial direction of the roller.

[0003]

[Problems to be solved by the device]

 However, with the peeling claws arranged in this way, when the size of the transfer paper to be peeled is large (for example, A0 or A1 size), the leading edge of the transfer paper collides with a plurality of peeling claws at one time, and The paper may be impacted, causing the unfixed toner image to bleed or blur.

[0004]

[Means for Solving the Problems]

 The present invention has been made in view of the above points, and a fixing device according to the present invention is a fixing device having a plurality of peeling claws for peeling transfer material from a roller surface, wherein the plurality of peeling claws are arranged in the axial direction of the roller. The feature is that they are arranged so that they are sequentially delayed in the radial direction based on a part.

[0005]

[Action]

 By such means, the transfer paper that is in close contact with the roller surface is partially peeled in the width direction by the first peeling claw, and is then peeled by the other peeling claws so as to sequentially spread in the width direction. ..

[0006]

【Example】

 Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 to 3 show a preferred embodiment of the present invention, in which 1 is a heating roller which rotates in the direction of an arrow, and a pressing roller 2 is arranged so as to press the transfer paper and press it against the heating roller. Is provided. The heating roller 1 is formed by coating the outer surface of a hollow aluminum roller 11 with an offset preventive material 12 such as Teflon, and a rod-shaped heater 13 is arranged inside the hollow. Further, the pressure roller 2 has a layer 22 made of a heat-resistant material having appropriate elasticity such as silicon rubber on the outer peripheral surface of the hollow aluminum roller 21 so that it is pressed against the heating roller by a biasing means (not shown). It is energized by and is driven by the heating roller by friction. As is well known, an anti-offset liquid is applied to the surface of the heating roller as needed. An appropriate temperature control device controls the heater 13 to be turned on / off to constantly maintain the heating roller at an appropriate temperature.

The transfer paper to be fixed is supplied to the nip between the heating roller 1 and the pressure roller 2 along the guide 3 while carrying the unfixed toner image on the upper surface, and the toner image is formed when passing through the nip. It is fused and fixed on the transfer paper. The transfer paper after fixing is fed in close contact with the surface of the heating roller 1, and is peeled from the surface of the heating roller 1 by a plurality of peeling claws 4 arranged with their tips in contact with the surface of the heating roller 1. The peeled transfer paper is then discharged outside the machine by the discharge roller pair 5.

In order to minimize the impact on the transfer paper at the time of peeling, the peeling claws 4 are arranged so as to be sequentially delayed in the radial direction with reference to a part of the heating roller 1 in the axial direction. 2 and 3 show an example of this arrangement. The arrow A in the figure indicates the rotation direction of the heating roller 1. In FIG. 2, the peeling claw 4 positions the first peeling claw 41 with reference to the center of the heating roller 1 in the axial direction, and then the second and third peeling claws are sequentially delayed toward both ends in the radial direction. Place the nails. Further, in FIG. 3, the first peeling claw 41 is positioned with reference to one end side of the heating roller 1, and then the second and third peeling claws are arranged so as to be sequentially delayed in the radial direction toward the other end. ..

Although the arrangement of the peeling claws with respect to the heating roller 1 has been described in the above example, even when the peeling claws are arranged with respect to the pressure roller 2, the arrangement of the peeling claws is the same as that of the above-described example. Have an effect.

[0010]

[Effect of the device]

 According to the fixing device of the present invention, even in the case of a large-sized transfer paper, the impact at the time of peeling can be minimized, and the bleeding or blurring of the toner image can be eliminated.

[Brief description of drawings]

FIG. 1 is a side sectional view showing an example of a fixing device according to the present invention.

FIG. 2 is a schematic front view showing an example of an arrangement of peeling claws according to the present invention.

FIG. 3 is a schematic front view showing another example of the arrangement of the peeling claws according to the present invention.

[Explanation of symbols]

 1 Heating Roller 2 Pressure Roller 3 Guide 4 Peeling Claw 5 Discharge Roller

Claims (3)

[Scope of utility model registration request] 1. A fixing device having a plurality of peeling claws for peeling a transfer material from a roller surface, wherein the plurality of peeling claws are arranged so as to be sequentially delayed in a radial direction with reference to a part of an axial direction of the roller. A fixing device characterized in that 2. The fixing device according to claim 1, wherein the peeling claws are arranged so as to be sequentially delayed in the radial direction toward the end with respect to the axial center of the roller. 3. The fixing device according to claim 1, wherein the peeling claws are arranged so as to be sequentially delayed in the radial direction from the one end side of the roller toward the other end.