JPS61176965A - Printing device - Google Patents

Abstract

PURPOSE:To eliminate the possibility of touching the heated part of a fixing device with operator's hand when a jam paper is inspected, by providing a protective cover which covers the heat roller type fixing device under a freely openable and closable condition. CONSTITUTION:When a jam of paper is inspected, an operator opens an outside door (not shown in the figure) and inspects a printing paper carrying passage from an opened section 18a. If necessary, the operator lowers the frame 80 of a carrying system and opens the carrying passage for making inspection. Jammed paper at locations other than a fixing device is taken out by directly inserting his hand. When paper jamming occurs in the fixing device, the operator opens a protective cover 19 in the direction shown by the arrow around a hinge 19a and takes out the jammed paper without touching the heated parts of a heat roller 91 and press roller 90. When the protective cover 19 is constituted of a transparent material, existence of jammed paper in the fixing device can be confirmed with the protective cover 19 being closed.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an electronic printing device that performs printing by developing a latent image after forming a latent image such as electrophotography or electrostatic recording. The present invention relates to a printing device that can ensure safety during inspection work on a heat roller type fixing device used.

2. Description of the Related Art Printing devices such as copying machines and recording devices that use electrophotographic technology or electrostatic recording technology are widely used.

In printing devices that use such electrophotography, an electrostatic latent image is formed, and a developing device is used to convert this into a visible image. Generally, a developing device that uses powder developer is used. Furthermore, a fixing device is used to fix this powder image (toner image).

[Conventional technology]

For example, in the electrophotographic apparatus shown in FIG. 7(A),
A charger 2 is installed around a photosensitive drum 1 having a photosensitive layer on its surface.
A developing device 3, a transfer device 4, a paper separator 5, a cleaner section 6, and a static eliminator 7 are arranged.

After the photosensitive drum 1 rotating clockwise is uniformly charged by the charger 2, the optical unit (
12 (laser light source, etc.), an electrostatic latent image corresponding to the light image is formed on the photosensitive drum 1, and a visible image (toner image) is formed by the magnetic brush type developer 3.
is developed. Further, the paper taken out from the paper feed cassette 11 by the pink roller 10 is guided by the standby roller 14 to the lower guide 13a in synchronization with the rotation of the photosensitive drum 1 and sent to the transfer device 4, whereby the image on the photosensitive drum 1 is transferred. The transferred paper is transferred to paper, and the transferred paper is transferred to A of the paper separator 5.
C, it is separated from the photosensitive drum 1 by static elimination, guided to the lower guide 13b, sent to the heat roller type fixing device 9 by the feeding roller 15,
After being heated and fixed, it is sent to the stacker 17 by the discharge roller 1G and stored.

On the other hand, after the photosensitive drum 1 is transferred to paper, it is cleaned by a cleaner section 6, and then the surface is neutralized by a static eliminator 7, and the process starting from the charger 2 is repeated again.

The fixing device 9 used in such an electrophotographic apparatus is a heat roller type fixing device with a simple structure. Consisting of a roller 90 and a cover 92 that prevents heat from the heating roller 91 from leaking to the outside,
A sheet of paper having a toner image is fed while the toner image surface is pressed against a heating roller 91 by a pressure roller 90, and the toner image is heated and melted to be fixed.

In such an electrophotographic apparatus, when a paper jam occurs, it is necessary to open the paper conveyance path, and the standby roller 14, lower guides 13a, 13b, transfer device 4, paper separator 5, and feed roller 15 are placed on the conveyance system frame 8. The conveyance system frame 8 was lowered as shown in FIG. 7(B) to open the paper conveyance path.

On the other hand, if the fixing device 9 is an integrated type, it does not move as shown in FIG. 7(B), and if it is not an integrated type, the pressure roller 90 side is downwardly moved, similar to the frame 8.

In the event of a paper jam like this, the operator opens the outer door and inspects the inside, but with the outer door open, the
As shown in the figure, each component is supported and covered by an internal frame 18, and a portion indicated by 18a is left open for taking out sheets or performing maintenance work. Fuser 9
In the case of a non-integrated type, as shown in FIG. 8(A), the internal frame 18 covers the heating roller 91, and the pressure roller 90 and the conveyance system frame 8 are exposed at the open part 18a. On the other hand, the one with integrated fixing device 9 is shown in Fig. 8(B).
As shown in FIG. 2, the fixing device 9 is not covered by the frame 18, and the fixing device 9 and the transport system frame 8 are exposed at the open portion 18a.

The opening portion 18a allows the operator to see the state of paper jam, and also allows the operator to reach inside to remove jammed paper and perform maintenance such as cleaning each part.

In this type of printing apparatus, the temperature of the fixing device 9 is around 180° C., and if touched by hand, there is a risk of burns or the like.

For this reason, in the past, a warning display such as "Caution at High Temperature" was provided on the frame 18 near the fuser 9 as shown in FIG. Insulating material is pasted on the exterior surface of the machine, and a nameplate reading "Caution at high temperatures" is also installed.
The operator was warned.

[Problem that the invention seeks to solve]

However, in the former method, the conventional method only displays a warning message, so if you are distracted by the jammed paper when opening the outer door and overlook this, you can remove the jammed paper on the conveyance path, especially the jammed paper in the fuser. There is a problem in that it is difficult to prevent burns or the like from directly touching the heating roller 91 or the like due to inadvertence.

On the other hand, in the latter conventional method, the exterior surface is protected by a heat insulating material, so it is safe to touch this surface, but in order to remove jammed paper from the fuser, you must put your hand in from the side of the fuser. Similarly, if you overlook the warning signs, you may inadvertently come into direct contact with the heating roller, etc.
There was a problem in that it was difficult to prevent burns and the like.

[Means for solving problems]

SUMMARY OF THE INVENTION An object of the present invention is to provide a highly safe printing apparatus that can prevent an operator from taking careless actions toward a fixing device when inspecting the inside of the apparatus due to a paper jam or the like.

For this reason, the present invention includes a latent image forming means for forming a toner image, a conveying means for conveying a medium, and a toner image of the latent image forming means being conveyed in the middle of a medium conveying path by the conveying means. In a printing device having a transfer means for transferring the toner image onto a medium, and a hot roller type fixing device for fixing the toner image transferred to the medium, a protective cover is provided to cover the hot roller type fixing device, and the protective cover is provided. It is characterized by being configured so that it can be opened and closed freely.

[Effect]

In the present invention, a protective cover is provided to cover the heated roller type fuser, and the heated part is covered to prevent the operator from accidentally touching the heated part, and the protective cover is configured to be openable and closed. When accessing the fixing device, the operator is given the operation of opening the protective cover to alert the operator before inspection, thereby achieving safety regarding the heated parts.

〔Example〕

Hereinafter, the present invention will be explained in detail with reference to Examples.

FIG. 1 is a configuration diagram of an embodiment of the present invention, and FIG. 2 is a sectional view of a main part thereof.

In the figure, the same parts as those shown in Figs. 7 and 8 are indicated by the same symbols, and 19 is a protective cover made of a heat-insulating plate, such as plastic, and at least in the heated part. It is large enough to cover a certain heating roller 91 and pressure roller 90, and is releasably attached to the frame 18 by a hinge 19a, and a warning "Caution for high temperature" is displayed on the surface. Reference numeral 80 denotes a transport system frame, which supports the transport systems 13a and 13 as described later in FIG.
b, 14.15 and the pressure roller 90.

To explain the operation of this configuration, when a paper jam occurs, the operator opens the outer door (not shown) and inspects the paper conveyance path through the open portion 18a. If necessary, lower the transport system frame 80 as shown in FIG.
Remove jammed paper by inserting your hand directly. on the other hand,
If the paper is jammed in the fuser 9, in order to remove it, open the protective cover 19 around the hinge 19a in the direction of the arrow in Figure 2 (toward the front in Figure 1). It can be confirmed that the heating roller 91
The jammed paper can be taken out without touching the heated parts such as the press roller 90 and the press roller 90.

If the protective cover 19 is made of a transparent material, the presence or absence of jammed paper in the fixing device 9 can be confirmed with the protective cover 19 closed.

After removing the jammed paper in this manner, the protective cover 19 is closed, the transport system frame 80 is returned to its original position above, and the outer door is closed to complete the jamming operation.

Therefore, when inserting a hand into the fixing device 9, the protective cover 19 is opened after confirming that it is dangerous, thereby preventing burns due to careless actions of the operator.

Next, the frame 80 that supports the pressure roller 90 described above will be explained with reference to FIGS. 3, 4, and 5.

Figure 3 is an internal configuration diagram of the configuration shown in Figure 1, and Figure 4 is an internal configuration diagram of the configuration shown in Figure 1.
FIG. 5 is a sectional view of a main part of the configuration, and FIG. 5 is an explanatory diagram of the operation of the configuration of FIGS. 3 and 4.

In the figure, the same parts as those shown in FIG.
12c is a reflecting mirror that reflects the light image from the polygon mirror 12b to the photosensitive drum 1. 93 is a separating claw of the fixing device 9 for separating the paper and the heating roller 91; 94 is a cleaner for removing toner adhering to the heating roller 91;
Reference numeral 5 denotes a temperature detection section, which is composed of a thermistor and is used to detect the temperature of the heating roller 91 and control the halogen lamp inside the heating roller 91 to keep the heating temperature constant. Reference numeral 80 denotes the above-mentioned transport system frame, which holds the standby roller 14, lower guides 13a, 13b, transfer device 4, paper separator 5, and delivery roller 15, and also holds the above-mentioned second
A device that holds the pressure roller 90 with the configuration shown in the figure,
Reference numeral 81 denotes a hinge, which allows the transport system frame 80 to rotate about the support shaft with respect to the photosensitive drum 1, which is a latent image forming means.

In the configurations shown in FIGS. 3 and 4, the pressure roller 90 is provided on a frame 80 of the conveyance system, and the frame 80 can be rotated by a hinge 81 as shown in FIG. The pressure roller 90 can move up and down with respect to the photosensitive drum 1 integrally with the paper conveyance system.

Therefore, when the transport system frame 80 is rotated about the hinge 81 by a vertical movement mechanism (not shown) as shown in FIG. 4(B), the pressure roller 90 of the fixing device 9 is The heating roller 9 lowers with the paper conveyance system.
1, and the paper conveyance path to the fixing device 9 is opened.

Therefore, the inspection operation when a paper jam occurs only needs to be done once, and the pressure roller 90 can be easily replaced.

Note that it is sufficient to use a well-known vertical movement mechanism as a mechanism for vertically moving the transport system frame 80.

Of course, the frame 8 in which the aforementioned pressure roller 90 is integrated
The present invention can be applied not only to the configuration shown in FIG. 8A but also to the configuration in which the fixing device 9 and the transport frame 8 are not integrated as shown in FIG. 8(A).

Next, other embodiments of the present invention will be described.

FIG. 6 is a configuration diagram of another embodiment of the present invention, and FIG. 8 (B
) is an example in which a protective cover is applied to the integrated fuser.

In the figure, the same parts as shown in Figures 7 and 8 are indicated by the same symbols, and 20 is a protective cover made of plastic or other heat-insulating material similar to the embodiment shown in Figure 1 above. Its size is small (enough to cover the integrated fuser 9, and the hinge 20 is small).
A is releasably attached to the frame 18 as in FIG. 2, and a warning "Caution for high temperature" is displayed on the surface.

To explain the operation of such a configuration, when a paper jam occurs, the operator opens the outer door (not shown) and opens the opening section 18 as in the above-described embodiment.
Inspect the paper conveyance path from a, and if necessary, lower the frame 8 downward to open the conveyance path and perform the inspection, and remove jammed sheets other than those in the fixing device 9 by directly inserting your hands. On the other hand, if there is a paper jam in the fuser 9, in order to remove it, open the protective cover 20 in the direction of the arrow in Figure 2 (towards you in Figure 6) centering on the hinge 20a. It can be confirmed that the jammed paper is removed without touching the heated parts such as the heating roller 91 and the pressure roller 90.

In this case, the width of the protective cover 20 is wider on both sides than the width of the fuser 9, so even if you try to remove the jammed paper from the fuser 9 without opening the protective cover 20, the protective cover 20 will get in the way. This can be prevented by ensuring that the jammed paper in the fixing device 9 cannot be taken out unless the protective cover 20 is opened. Further, as in the previous embodiment, if the protective cover 20 is made of a transparent material, the presence or absence of jammed paper in the fixing device 9 can be confirmed with the protective cover 20 closed.

After removing the jammed paper in this manner, the protective cover 20 is closed, the transport system frame 8 is returned to its original position above, and the outer door is closed to complete the jamming operation.

In the above-described embodiment, the frame 80 is moved up and down by rotation of the frame 80, but a vertical movement mechanism that slides the frame 80 in parallel up and down may be used. Furthermore, if the optical unit 12 is replaced with a document scanner of a copying machine, it can also be applied to a copying machine. Furthermore, if the photosensitive drum 1 is constituted by an insulating drum and provided with an electrostatic recording pin electrode, it can also be applied to a transfer type electrostatic recording device.

Although the present invention has been described above using one embodiment, the present invention can be modified in various ways according to the gist of the present invention, and these are not excluded from the present invention.

〔Effect of the invention〕

As explained above, according to the present invention, a latent image forming means for forming a toner image, a conveying means for conveying a medium,
a transfer unit that transfers the toner image of the latent image forming unit onto the medium being conveyed in the middle of the medium conveyance path by the conveyance unit;
A printing device having a hot roller type fixing device for fixing the toner image transferred to the medium, characterized in that a protective cover is provided to cover the hot roller type fixing device and the protective cover is configured to be openable and closable. This has the effect that there is no risk of accidentally touching the heated part of the fuser when checking for paper jams, and it also has the effect of forcing the user to perform the artificial action of opening the protective cover when approaching the fuser. This has the effect of allowing the operator to operate the fuser after confirming that it is dangerous, and prevents burns caused by the heat of the fuser due to careless actions of the operator, providing a highly safe printing device. can do. In addition, the means for this purpose is relatively simple, such as a protective cover, and can be realized easily and inexpensively, which is an excellent practical effect.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram of an embodiment of the present invention, FIG. 2 is a sectional view of a main part of the configuration in FIG. 1, and FIG. 3 is an internal configuration diagram of the configuration in FIG. 1.
FIG. 4 is a sectional view of the main part of the configuration shown in FIG. 3, FIG. 5 is an explanatory diagram of the operation of the configuration shown in FIG. 3, FIG. 6 is a configuration diagram of another embodiment of the present invention, and FIG. 7 is a configuration diagram of the printing device. , FIG. 8 is a conventional configuration diagram. In the figure, 1-photosensitive drum (latent image forming means), 4-transfer device, 8.80--conveying system frame, 9--thermal roller type fixing device, 14.15--conveying roller (@ conveying means ), 13
a, 13 b-lower guide (conveyance means), 18-internal frame, 18a--opening section, 19.20-protective cover, 1
9a, 20a--hinge portion.

Claims (1)

[Claims] A latent image forming means for forming a toner image, a conveyance means for conveying a medium, and a transfer means for transferring the toner image of the latent image forming means onto the medium being conveyed during the medium conveyance path by the conveyance means. and a hot roller type fixing device for fixing the toner image transferred to the medium, in which a protective cover is provided to cover the heated roller type fixing device and the protective cover is configured to be openable and closable. A printing device featuring: