JPH04208975A - Thermal fixing device for electrophotographic 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] [Summary] Regarding a heat fixing device of an electrophotographic device that uses a heat roller to fix a toner image on recording paper, when an operator opens a case surrounding the heat roller and inserts his/her hand into the heat roller, The purpose of this is to prevent the risk of burns caused by a heat roller that rotates with recording paper sandwiched between it and a backup roller that is pressed into contact with the heat roller, and a case that surrounds both of the rollers and that can be opened and closed. and a heat roller cover that moves in conjunction with the opening/closing operation of the case to a position covering the exposed portion of the heat roller when the case is opened.

[Industrial application field]

The present invention relates to a heat fixing device for an electrophotographic apparatus that uses a heat roller to fix a toner image on recording paper.

Since the toner image developed on the recording paper easily collapses if left as it is, it is necessary to press and heat it with a heat roller to fix it.

[Conventional technology]

FIG. 4 shows a heat fixing device of a conventional electrophotographic apparatus. A backup roller 52 is in pressure contact with the fixing heat roller 51, and the recording paper 100 is conveyed while being sandwiched therebetween.

The heat roller 51 is surrounded by a fixed case 53 from below, and the hack-up roller 52 is surrounded by a movable case 54 from above. The recording paper 100 is stored in both cases 53.
54.

A cleaning felt 55 is provided in contact with the heat roller 51 in order to supply an oil film to the heat roller 51 and wipe away toner particles and the like.

When the recording paper 100 is fed through such a fixing device, a paper jam may occur as shown in FIG. 4.

In such a case, conventionally, as shown in FIG. 5, the movable case 54 is lifted upward and both cases 53.5
The operator would remove the recording paper 100 by widening the gap between the spaces 4 and 4 and inserting his/her hand into the space.

Further, when replacing the cleaning felt 55, the operator similarly opens the cases 53 and 54 and inserts his hand inside.

[Problem to be solved by the invention]

However, when you open the case 53 or 54 and insert your hand inside, the heat roller 51 is exposed inside.
You may end up touching the heat roller 51 with your hand. In this case, since the heat roller 51 is generally heated to about 200° C., there is a risk of instantaneous burns on the hands.

The present invention eliminates such conventional drawbacks and provides a safe heat fixing device for an electrophotographic apparatus in which an operator is not at risk of getting burned when opening the case surrounding the heat roller and inserting his/her hand into the heat fixing device. With the goal.

[Means to solve the problem]

In order to achieve the above object, the heat fixing device of the electrophotographic apparatus of the present invention has a recording paper 100 placed between it and a backup roller 1 pressed against it, as shown in FIG. 1 for explaining an embodiment. A heat roller l that rotates while sandwiching the
A case 2.3 is provided surrounding both the rollers 1 and 11 so as to be openable and closable, and in conjunction with the opening and closing operations of the cases 2 and 3, when the cases 2 and 3 are opened, the heat roller l
Heat roller cover 5 moves to a position covering the exposed part of
It is characterized by having the following.

The heat roller cover 5 is rotatably provided coaxially with the heat roller l, and is connected to the cases 2 and 3 by a connecting member 7, and the heat roller cover 5 is opened by opening the cases 2 and 3. may be rotated and moved to a position covering the exposed portion of the heat roller l.

Further, the cases 2 and 3 are formed separately into a fixed case 2 surrounding the heat roller l and a movable case 3 surrounding the backup roller 11, so that the backup roller 11 moves together with the movable case 3. May be placed.

[Effect]

When the cases 2 and 3 are opened, the heat roller cover 5 moves to a position that covers the exposed portion of the heat roller 1 in conjunction with the opening of the cases 2 and 3.

〔Example〕

Examples will be described with reference to the drawings.

FIG. 3 shows an electrophotographic printer device.

However, the present invention can also be applied to copying machines and the like.

A photosensitive drum 22 is provided near the center of the printer and rotates to transfer image information onto the recording paper 100 onto its outer peripheral surface. Around the photosensitive drum 22, a pre-charger 31, a latent image forming means 32 consisting of a light emitting diode array, etc., a developing device 33, a transfer device 34, a static eliminator 35, and a cleaner 36 are arranged. There is.

The recording paper 100 stacked on the hopper 40 is supplied to the first paper feed roller (standby roller) 42 by the rotation of the pick roller 41 that is in pressure contact with the recording paper 100, and a print command is issued while in contact with the first paper feed roller (standby roller) 42. wait for.

In order to allow the recording paper 100 to pass through while contacting the outer peripheral surface of the photosensitive drum 22, a second
and a third paper feed roller 23. ■ is placed. Of these, the third paper feed roller 1 provided after the photosensitive drum 22 is a heat roller for thermal fixing, and is a heat roller for thermal fixing.
It plays the role of a fixing device that fixes the toner image on the surface.

Reference numeral 11 denotes a backup roller that rotates while being pressed against the heat roller.

The photosensitive drum 22 rotates as shown by the arrow in FIG. 3, and the recording paper 100 is supplied from the hopper 40 side by a paper feed roller 42 via a conveyance path 43, and then transferred to a transfer section 34 by a second paper feed roller 23. It is supplied in synchronization with the rotation of the photosensitive drum 22.

On the other hand, the photosensitive drum 22 is uniformly charged by the front charger 31, an electrostatic latent image is formed by the latent image forming means 32, and then the latent image is made into a toner image by the developing device 33. The toner image is transferred onto the recording paper 100 by the transfer device 34.

Next, the recording paper 100 is conveyed to the left, and heated while being conveyed to the left while being sandwiched between a heat roller serving as a heat fixing device and a backup roller 11, thereby fixing the toner image. Then, the recording paper 10 that has been fixed
0 is discharged to the stacker 45 by the discharge roller 44.

After the transfer is completed, the surface of the photosensitive drum 22 is neutralized by a static eliminator 35, and the remaining toner is cleaned by a cleaner 36.

FIG. 2 shows the fuser section.

The heat roller l is surrounded by a fixed case 2 from below. A cleaning felt 4 for supplying an oil film to the heat roller I and wiping off toner particles and the like is arranged in the fixed case 2 so as to come into contact with the heat roller I.

The backup roller 11 is surrounded by the movable case 3 from above, and is rotatably supported by the movable case 3 at both ends. Therefore, if the movable case 3 is moved, the backup roller 11 will also move with it.

A gap is formed between the upper end of the fixed case 2 and the lower end of the movable case 3, and the recording paper 100 passes through the gap.

Both ends of a heat roller cover 5 are rotatably supported on the central axis of the heat roller I.

The heat roller cover 5 covers the entire length of the outer peripheral surface of the heat roller 1 in an area slightly smaller than half the circumference so as not to interfere with the recording paper 100 and the cleaning felt 4.

Further, the lower end of the movable case 3 and the lower end of the heat roller cover 5 are connected by a connecting wire (connecting member) 7.

The movable case 3 can be moved upward as shown in FIG. At that time, within the range in which the rib 8 protruding from the movable case 3 can move along the inside of the guide hole 9,
The movable case 3 moves in the vertical direction.

By lifting the movable case 3 upward, the space between the movable case 3 and the fixed case 2 is widened.

Therefore, insert your hand into the gap and insert the recording paper 100.
can be taken out or the cleaning felt 4 can be replaced.

However, by lifting the movable case 3 upward,
The connecting wire 7 is pulled upward, thereby rotating the heat roller cover 5. As a result, the heat roller cover 5 covers the exposed portion of the upper surface of the heat roller 1, as shown in FIG.

Therefore, even if the operator inserts his hand between the cases 2 and 3, his hand will not touch the heat roller l, thereby eliminating the risk of burn injury.

〔Effect of the invention〕

According to the heat fixing device of the electrophotographic apparatus of the present invention, when the case surrounding the heat roller is opened, the exposed portion of the heat roller is covered by the heat roller cover, so that the heat roller section can be used for removing recording paper, etc. It has excellent effects such as there is no risk of getting burned even if you insert your hand.

A 1m $ /7-141111m F Bone k
tE+ FIG. 2 is a sectional view of the embodiment with the cover closed, FIG. 3 is a schematic side view of the printer of the embodiment, FIG. 4 is a sectional view of the conventional example with the cover closed, and FIG. , is a cross-sectional view of the conventional example with the cover open.

In the figure, 1--heat roller; 2...Fixed case (case), 3...Movable case (case), 5...Heat roller cover, 7... Connection wire (connection member), 11...Backup roller.

Figure 1 is a sectional view of the embodiment with the cover open, ↑ 9! Noh mask in cover state of Kae1 Figure 1 Actual results? 10 real bar collection Figure 2 Yellow boat glass 071j Nfu's loan 1 Figure 3

Claims (1)

[Claims] 1. A heat roller (100) that rotates with a recording paper (100) sandwiched between it and a backup roller (11) pressed against it.
1), a case (2, 3) that surrounds both the rollers (1, 11) and is provided so as to be openable and closable; ) is opened, the heat roller cover (5) moves to a position covering the exposed portion of the heat roller (1).
) for an electrophotographic apparatus. 2. The heat roller cover (5) is rotatably provided coaxially with the heat roller (1), and is connected to the connecting member (7).
), and is connected to the case (2, 3) by an operation of opening the case (2, 3), and is rotated and moved to a position covering the exposed portion of the heat roller (1). Heat fixing device for electrophotographic equipment. 3. The above cases (2, 3) are the above heat roller (1)
The fixed case (2) surrounding the above-mentioned backup roller (
and a movable case (3) surrounding the movable case (11), and the backup roller (11) is arranged so as to move together with the movable case (3). vessel.