JPS5823627B2 - Paper ejection guide for heating fuser - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a paper discharge guide for a heat fixing device of a copying machine.

Generally, a copying machine uses a heat fixing device to fix a toner image formed on copy paper, and a paper discharge guide is provided on the copy paper exit side of the heat fixing device.

When the heat source of the heat fuser is turned on to start using the copying machine, even though the surrounding air is warmed, the paper ejection guide is at a low temperature, so there is no exposure to the paper ejection guide. A phenomenon occurs.

Furthermore, since the copy paper being passed through contains water, a large amount of water evaporates when passing through the heat fixing device, increasing the water vapor pressure around the paper ejection guide, thereby forming a space where dew condensation is extremely likely to occur.

In order to prevent the occurrence of this dew condensation phenomenon, conventionally, a plurality of wires are stretched over a support member so as to extend in the paper ejection direction and fixed by welding, and such a guide is incorporated into a copying machine.

That is, a wire having a small heat capacity and a large heat receiving area or heat dissipating area is used as the guide element, and a wide space is provided to obtain a large diffusion effect of water vapor generated from the transfer paper.

However, in such a paper ejection guide, since the guide element is made of wire, it is difficult to obtain high positional accuracy when welding it to the support member, and even after it is installed in a copying machine, it may cause errors. It has the drawback that it easily deforms when touched, and as a result, smooth paper ejection guidance is hindered.

The present invention has been made to eliminate the above-mentioned drawbacks, and will be described in detail below with reference to the drawings.

In FIG. 1, 1 is a heating roller and 2 is a pressure roller, which constitute a heating roller fixing device.

According to the present invention, as shown in FIG. 2, a band-shaped guide plate part 3B is integrally formed at one end of the plate-shaped leg part 3A, and is bent at right angles to the other end of the leg part 3A. The upper guide element 3, which is integrally formed with the mounting plate portion 3C extending as shown in FIG.

More specifically, in this upper guide element 3, a rectangular hole H is formed at the center of the rectangular plate to form two leg portions 3A, and the guide plate portion 3B is formed in a direction substantially perpendicular to the leg portions 3A. The mounting plate portion 3C extends and is bent at a right angle from one leg portion 3A, and the other ends of the leg portion 3A are connected by a connecting plate portion 3D, which is made of aluminum or the like.

The upper guide element 3 is mounted on the mounting plate portion 3C by a long support member so that the other side edge of the guide plate portion 3B, which is opposite to the protruding one side edge of the leg portion 3A, is downward. 4
A large number of upper guide elements 3 are arranged in parallel on the support member 4 by welding to the support member 4, and these guides are attached to the guide plate portion 3B on the copy paper exit side of the heating roller fixer.
is arranged inside the copying machine so as to extend along the paper ejection direction.

The present invention is constructed as described above, and the lower surface of the guide plate portion 3B of the guide element 3, that is, the other side edge surface S serves as a guide surface to guide the copy paper from the heating roller fixer.

In each of the upper guide elements 3 according to the present invention, both the leg portions 3A and the guide plate portions 3B can be easily formed into strip-shaped plate bodies, so that they have a small heat capacity and a large heat dissipation area. Therefore, it is possible to prevent dew condensation from occurring when the fixing device is started to be used.

Furthermore, the space around the paper ejection guide is expanded, providing a larger space for the diffusion of water vapor from the transfer paper, and the relative humidity around the paper ejection guide is reduced, making it possible to prevent dew condensation that occurs during paper copying. can.

Moreover, since each part of the guide element 3 is an integral rigid body, it is easy to set the position with high precision when welding the mounting plate part 3C to the support member 4, and foreign objects can easily be As a result, the guide surface of the guide plate portion 3B can be positioned along the desired guideline, and the copy paper can be smoothly and reliably ejected from the fixing device. I can do it.

In order to position the upper guide element 3 with respect to the support member 4, for example, the support member 4 may be provided with a bent portion 4A, and the end face of the connecting plate portion 3D of the guide element 3 may be brought into contact with the bent portion 4A. Accuracy can be obtained more easily.

Furthermore, as can be easily understood from the above description, the upper guide element 3 can be easily manufactured by simply punching and bending a single metal plate, and is extremely inexpensive.

Since the guide surface is the end surface S of the guide plate portion 3B, the contact area with the copy paper is small and the frictional resistance when the paper comes into contact is small, and the occurrence of paper ejection failure due to this large resistance is prevented. .

Although the upper guide has been described above, the same applies to the lower guide, where 5 is a lower guide element, 5A is a leg portion, 5B is a guide plate portion, 5C is a mounting plate portion, and 6 is a support member.

Furthermore, in the present invention, the guide element having the leg portions and the guide plate portion can be integrally formed by cutting and raising the plate-like portion constituting the support member 4 or 6, and in this way, welding or the like is not required. Therefore, there is no fear of positional deviation or the like.

As described above, the paper ejection guide for a heating fuser according to the present invention has an extremely simple structure, does not cause dew condensation, has high positional accuracy of the guide surface, eliminates the risk of displacement, and can be smoothly ejected as expected. There are great benefits that paper can achieve.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram when the present invention is applied to an upper guide and a lower guide, respectively, and FIG. 2 is an external view of the main parts of the upper guide in FIG. 1 when viewed in the direction of the arrow. 1... Heating roller, 2... Pressure roller, 3...
- Upper guide element, 3A... Leg portion, 3B... Guide plate portion, 3C... Mounting plate portion, 4, 6... Support member, 5... Lower guide element.

Claims (1)

[Claims] 1 Consists of a plurality of guide elements made of rigid material that are attached to the main body of the copying machine so as to be juxtaposed with each other, each guide element consisting of a plate-like leg portion and a guide plate portion integrally provided at the end of the leg portion, A paper ejection guide for a heat fixing device, wherein a copy paper guide surface is formed by an end surface of the guide plate portion.