JP2853914B2 - Image forming device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus having a fixing device for fixing and discharging an unfixed toner image on a recording material.

[0002]

2. Description of the Related Art Conventionally, as a fixing device in an image forming apparatus, a heat roller system generally comprising a fixing roller and a pressure roller and performing heat fixing by passing an unfixed toner image is generally used.

In other systems, a pressure fixing system in which heating is not performed, and recently, a fixing film system using a heating element having a low heat capacity and a heat-resistant thin film have appeared.

The most common type of jam in these fixing devices is a bellows-shaped jam (called an accordion jam) in the recording material discharge opening path from the nip. There is a case where the side (including the discharge device) is rotatably provided to expose and remove the nip. Also, a method of improving the operability of removing the recording material by reducing the pressing force of the pressing member or separating the pressing member in conjunction with the opening of the paper discharge unit has been used.

[0005]

However, in the above conventional example, since the jammed recording material is near the nip,
Some users have the disadvantage that the fixing roller and the pressure roller are erroneously damaged, and when the recording material is thin, it is torn off.

Furthermore, in the case of a jam wound around a pressure roller instead of the accordion jam as described above, the conventional example has few exposed portions and cannot be said to be processed very easily. In addition, since the temperature of the nip is naturally raised, it is very dangerous for the user.

As another jam clearing method, there is a crocodile method in which the apparatus main body is divided into upper and lower parts with a recording material conveying path as a boundary. Not suitable for models. Further, there is a device in which the lower portion of the apparatus is opened after the main body itself is in a standing state, but the operability of the user is very poor.

That is, as the jam of the recording material generated around the fixing device, there are the accordion jam and the jam wrapped around the pressure roller as described above. There was a problem of causing damage.

The present invention is to solve such a problem. That is, an object of the present invention is to provide an image forming apparatus capable of easily and surely performing jam processing in a fixing device.

[0010]

According to an aspect of the present invention, a pair of fixed members for nipping and conveying a recording material carrying an image are provided.
A fixing member and one of the fixing members, the other fixing unit
And openable closing member device for a body with a timber, the
Between the main unit and the floor when jamming recording materials.
Image forming apparatus in which a space is formed and the opening / closing member is opened
In the above, the opening and closing member is a device for forming the space.
It is designed to hold the main body .

[0011]

In the image forming apparatus having the above structure, the recording material
During sham processing, a space is formed between the main unit and the floor
When the opening and closing member is opened, the space is opened by the opening and closing member.
Since the device body is held for forming, separate holding means
No need to provide.

[0012]

EXAMPLES 1 and 2 show a first embodiment of the present invention. FIG. 1 shows a normal use state, and FIG. 2 shows a jam clearance state of the fixing unit.

1 and 2, reference numeral 1 denotes a document table;
Denotes a lens, 3 denotes a drum, 4 denotes a paper feed roller, 5 denotes a registration roller composed of a pair of rollers, 6 denotes a transfer unit, 7 denotes a transport belt, and 8 denotes a fixing device.

That is, the original table 1 is of a movable type, in which an image is copied by reciprocating the original table 1, and the image is latent-imaged on a drum 3 through a lens 2. Here, a toner image is formed by a developing unit (not shown).

The recording material is fed by a feed roller 4, conveyed from a registration roller 5 to a transfer section 6, the toner on the drum is transferred, and guided to a fixing device 8 by a conveyance belt 7.

The fixing device 8 of this reference example has a heating element 9 having a low heat capacity and an endless heat-resistant fixing film 10.

The pressure roller 11 rotates while being pressed against the heating element 9 by the pressure spring 12 via the fixing film 10. The recording material on which the unfixed toner image is placed passes through the recording material, so that the recording material is heated and fixed, and is discharged from the paper exit 13.

The pressure roller 11 is provided with respect to the apparatus main body.
It is included in the jam processing unit 14 which is an openable and closable member . The jam processing unit 14 is provided with an opening / closing lever 16 having a claw portion that fits with the main body protrusion 15. Normally, the protrusion 15 and the claw are fitted to prohibit opening.

Further, a holding lever 17 for separating the bottom of the main body from the floor is rotatably provided at the lower part of the main body. One end 17a of the holding lever 17 prevents the jam processing unit 14 from being opened.

That is, the jam processing unit 14 can be opened only when the holding lever 17 is in the jam processing posture (FIG. 2).

That is, as shown in FIG. 2, when a jam occurs, first, the holding lever 17 is rotated in a counterclockwise direction so that the main body is tilted with the paper supply side as a fulcrum, so that the main body and the floor are separated. To form a space. By operating the opening / closing lever 16, the jam processing unit 14 is opened to the space.

Next, after the jammed recording material is processed, if the operation reverse to the above-described operation is performed, the image forming operation can be performed again. In addition, the above-described holding lever 1
7. When the jam processing unit 14 is set at the position shown in FIG. 2, a power source may be turned off by providing a detection means such as a microswitch (not shown).

[0023] Figure 3 shows a second exemplary embodiment of the present invention, represents the lower portion of the apparatus main body, for details of other portions are omitted.

In the second embodiment , the holding lever 17 is of a protruding type, not of a rotating type. That is, the urging means 18 such as a spring is provided to maintain the jam clearance posture. As described above, when the apparatus main body is tilted, and when the document table is movable as in the first reference example , a document table dropping means is required, depending on the tilt angle. Of course, it may be linked to the holding lever 17.

[0025] Figure 4 shows a third exemplary embodiment of the present invention, represents the lower portion of the apparatus main body, for details of other portions are omitted.

In the third reference example , the holding levers 17A,
A plurality of 17Bs are provided so that the apparatus body is lifted horizontally.

[0027] Figure 5 shows a fourth exemplary embodiment of the present invention, represents the lower portion of the apparatus main body, for details of other portions are omitted.

In the fourth embodiment , the jam processing unit 14 is of a type in which the jam processing unit 14 protrudes in the discharge direction.

[0029] Figure 6 shows a fifth exemplary embodiment of the present invention, represents the lower portion of the apparatus main body, for details of other portions are omitted.

In the fifth reference example , the use of the slide member 20 improves the jam clearance and protects the upper unit.

FIG. 7 shows a first embodiment of the present invention.

In the first embodiment, since the apparatus main body is held by the jam processing unit 14 itself, the holding means can be omitted, and the operability is improved. In addition, by providing the fixing shutter 21 that opens in conjunction with the jam processing operation, the upper unit is protected, and the safety is further improved without the user touching the high-temperature portion.

In the first embodiment , a fixing film system is used as the fixing device 8. In particular, in the case of the fixing film system, the fixing film 10 as an upper unit is a thin film, and a sharp film such as tweezers is used. This is because when the jam processing is performed by a member, the fixing film 10 is significantly damaged, such as being torn, so that the jam processing method as in the first embodiment is effective.

However, the present invention is also effective in a heat roller system and a pressure fixing system.

The jam processing unit may include not only a pressing member but also a conveyance guide for guiding the recording material to the nip and a paper discharging means for discharging the recording material from the nip to the outside of the apparatus main body. The opening angle and the distance to be separated are set according to the size of each device.

[0036]

As described above, according to the present invention,
When clearing recording materials, clear the space between the main unit and the floor.
It is not necessary to particularly provide a means for forming .

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a use state of a first reference example of the present invention.

FIG. 2 is a side cross-sectional view showing a jam clearance state of the apparatus of FIG.

FIG. 3 is a side view showing a second reference example of the present invention.

FIG. 4 is a side view showing a third reference example of the present invention.

FIG. 5 is a side view showing a fourth reference example of the present invention.

FIG. 6 is a side view showing a fifth reference example of the present invention.

FIG. 7 is a side cross-sectional view showing a jam clearance state according to the first embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 8 ... Fixing device 9 ... Heating body 10 ... Fixing film 11 ... Pressure roller 14 ... Jam processing unit 16 ... Opening / closing lever 17 ... Holding lever 18 ... Biasing means 19 ... Link member 20 ... Slide member 21 ... Fixing shutter

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G03G 13/20 G03G 15/00 550 G03G 15/20

Claims (1)

(57) [Claims] An apparatus for nipping and conveying a recording material bearing an image.
A pair of fixing members, one of which comprises the fixing member
An opening / closing member that can be opened and closed with respect to an apparatus main body having a fixing member
When the jam of the recording material is cleared, the apparatus body and the floor surface
An image form in which a space is formed between and the opening and closing member is opened
In the forming apparatus, the opening / closing member holds the apparatus main body to form the space.
An image forming apparatus.