JPS6030760Y2 - Fusing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electronic copying machine, and more particularly to an improvement in a fixing device for fixing a toner powder image obtained on copy paper.

In an electronic copying machine, the toner powder image obtained on the copy paper, which is the toner image support, can be most efficiently fixed by:
This can be said to be due to the heating and pressurizing method.

Conventionally, a fixing device as shown in FIGS. 1 and 2 is used.

That is, 1 is a heating roller connected to a drive source (not shown) and rotatably supported.

Reference numeral 2 denotes an electric heater housed within the heating roller 1.

Reference numeral 3 denotes a pressure roller that is pivotally supported to be able to move toward and away from the heating roller 1.

4a is an upper guide plate, 4b is a lower guide plate, and 5a and 5b are conveyance rollers that roll into contact with each other.

Reference numeral 6 denotes a peeling claw rotatably supported approximately at the center, and a claw portion 6a provided at one end of the peeling claw 6 is slid onto the heating roller 1 by the elastic force of a tension spring 7 stretched at the other end. come into contact with

Reference numeral 8 denotes a blade made of an elastic material supported by a blade supporter 9, and the edge of the blade comes into sliding contact with the heating roller 1.

Thus, the conveyed copy paper P is held between the heating roller 1 and the pressure roller 3, and the heating roller 1 heats the copy paper P by the heat generation action of the electric heater 2.

The claw portion 6a of the peeling claw 6 peels the copy paper P from the heating roller 1, and the blade 8 scrapes off the toner remaining on the heating roller 1.

However, in the fixing device configured in this manner, the upper and lower guide plates 4a and 4b are fixed.

Therefore, if the copy paper P is jammed due to some reason such as poor peeling or skew, the upper guide plate 4a becomes an obstacle and is difficult to remove.

Therefore, a structure was considered in which the upper guide plate 4a could be freely rotated, but when it was rotated, it would come into contact with the tension spring 7, so there was no margin in the design.

The present invention was developed in view of the above circumstances, and its purpose is to provide a fixing device that can be freely displaced by a peeling claw or a blade opening/closing member, thereby facilitating maintenance and inspection work. It is something to do.

An embodiment of the present invention will be described below with reference to FIGS. 3 to 5.

In the figure, 11 is a hollow pipe-shaped heating roller connected to a drive source (not shown).

Inside this heating roller 11 is an electric heater 12 which is a heating source.
is accommodated.

Reference numeral 13 denotes a pressure roller, both ends of which are rotatably supported by rotary levers (not shown).

Therefore, the pressure roller 13 can be used as the heating roller 1 as needed.
It is designed so that it can be connected to and separated from 1.

14 is a peeling claw, 15 is a blade, and 16 is an upper conveyance guide plate, all of which are supported by a support 17 that will be described later.

That is, reference numeral 18 denotes a substrate 18 which is a part of the copying machine main body A that pivotally supports both ends of the heating roller 11, and a holder 19 is attached to a portion of the substrate 18 above the heating roller 11.

This holder 19 is provided with a stopper stepped portion 20, and a bracket 22 is rotatably supported via a stepped screw 21.

Since the bracket 22 is installed on both holders 19 and its upper end is pivotally supported, its own weight is transferred to the end edge 2.
2a comes into contact with the stopper step portion 20.

The bracket 22 is rotatable only in the direction of the arrow A in the figure, that is, in the direction in which the end edge 22a moves away from the stopper step 20.

The peeling claw 14 is connected to a support shaft 2 installed on the bracket 22.
3, and is elastically biased by a torsion spring 24 engaged with this support shaft 23 so that the claw portion 14a comes into sliding contact with the peripheral wall of the heating roller 11.

The blade 15 is made of an elastic material such as a silicone rubber plate, and is integrally molded with the blade holder 25.

The blade holder 25 is screwed onto a part of the bracket 22 and the blade 1
The end edge of 5 is elastically biased so as to come into sliding contact with the heating roller 11.

The range biased by the torsion spring 24 is within the range of the elongated hole 26 formed in the screwed portion.

The lower end surface of the bracket 22 also serves as the upper conveyance guide plate 16, and a downwardly protruding guide piece 16a is attached thereto.

Further, a rubber piece 27 is attached to the lower end surface of the bracket 22, that is, on the upper conveyance guide plate 16.

29 is the knob.

The support body 17 constructed in this manner is elastically biased by a torsion spring 30 which is a spring elastic body.

That is, as shown in FIG. 5, a torsion spring 30 is fitted into the rod portion of the stepped screw 21, one end of which engages the holder 19, and the other end engages the bracket 22.

Therefore, the elastic force of the torsion spring 30 is in a counterclockwise direction around the bracket 22.

The end edge 22a is biased to rotate in a direction away from the stopper step portion 20.

On the other hand, 31 is an upper lid serving as an opening/closing member.

This upper lid 31 constitutes a part of the upper surface of the copying machine main body A, and is supported by a pivot pin 32 so as to be openable and closable.

A presser rod portion 32 is provided on the free end side of the upper lid 31 .

Since this presser rod portion 32 protrudes in a position opposite to the rubber piece 27, when the upper lid 31 is closed, the support rests on the rubber piece 27, and the elastic force of the torsion spring 30 is applied by its own weight. The bracket 22 is regulated in a predetermined position against the force.

However, when the upper cover 31 is opened, the force applied to the bracket 22 is removed, so that the elastic force of the torsion spring 30 acts on the bracket 22 to rotate it so as to follow the upper cover 31.

Further, lower conveyance guide plates 32ay32b are disposed before and after the rolling contact portion of the heating roller 11 and the pressure roller 13.

One lower conveyance guide plate 32b is connected to the upper conveyance guide plate 16.
There is a narrow gap between the guide piece 16a and the guide piece 16a.

A pair of conveying rollers 33, 33 are pivotally supported near these ends so as to roll into contact with each other.

Further, on this rotation direction side, there is a paper ejection tray 34 which is a paper ejection section.
is provided.

When the power is turned on, the electric heater 12 generates heat and heats the heating roller 11 to a predetermined temperature.

The pressure roller 1 is moved at the same time that the copy paper P, which is a toner image support on which an unfixed toner powder image has been obtained through a well-known copying process, is guided to the lower conveyance guide plate 32a.
3 rolls into contact with the heating roller 11.

The copy paper P is held between the heating roller 11 and the pressure roller 13, and is heated and pressed.

As a result, the toner powder image is fixed on the copy paper P.

The claw portion 14a peels the copy paper P from the heating roller 11, and releases the copy paper P from between the upper and lower conveyance guide plates 16 and 32b to the conveyance roller 3.
3 and 33, and is led to a paper discharge tray 34.

The blade 15 scrapes off toner that has been transferred and adhered to the heating roller 11 from the copy paper P to prevent offset.

If the copy paper P gets wrapped around the heating roller 11 or jams between the upper and lower transport guide plates 16, 32b for some reason, a warning lamp (not shown) flashes and the copying process is temporarily interrupted.

Then, the operation block opens the upper lid 31.

The bracket 22 is attached to the top cover 3 by the elastic force of the torsion spring 30.
1 and rotate in the direction of the arrow.

As the bracket 22 is pulled up, the claw portion 14a1 of the peeling claw 14 and the blade 15 are separated from the heating roller 11.
The upper conveyance guide plate 16 is spaced far from the lower conveyance guide plate 32b.

Therefore, the copy paper P is exposed and can be removed very easily.

When the removal work is completed, the upper lid 31 may be closed again.

The presser rod portion 32 contacts the rubber piece 27 and rotates the bracket 22 under the weight of the upper cover 31.

When the edge 22a of the bracket 22 contacts the stopper step 20 of the holder 19, the claw portion 14a and the blade 15 contact the heating roller 11, and the upper conveyance guide plate 16 closes a narrow gap with the lower conveyance guide plate 32b. Exists.

Therefore, it is possible to wait for the next fixing operation.

As explained above, according to the present invention, the support body is elastically biased by the spring elastic body so that the peeling claw or blade support body can be freely displaced, and the support body is elastically biased against the elastic force of the spring elastic body. Since a freely openable/closable opening/closing member that presses down the support is provided, even if copy paper gets wrapped around the heating roller or jams occur, this can be handled very easily, cleaning is also simplified, and work efficiency is improved. This effect is achieved.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the main parts of an electronic copying machine showing a conventional example of the present invention, Fig. 2 is a vertical sectional view thereof, Fig. 3 and the following shows an embodiment of the invention; FIG. 4 is a plan view of the main part, FIG. 4 is an enlarged vertical sectional view thereof, and FIG. 5 is an enlarged perspective view of section S in FIG. 3. A: Copy machine body, P: Copy paper, 1
1... Heating roller, 13... Pressure roller, 14... Peeling claw, 15... Blade, 34... Paper discharge section (paper output tray), 32b・
... (upper conveyance) guide plate, 17 ... support body, 30 ... spring elastic body (torsion spring), 31
...Top lid.

Claims (1)

[Scope of utility model registration request] A heating roller and a pressure roller that form an unfixed image and fix it by sandwiching the copy paper, and a peeling claw and a heating roller that slide into contact with the heating roller and peel off the copy paper that has finished fixing from the heating roller. a blade that scrapes off the toner; a support that displaceably supports the peeling claw or blade; and a spring elastic body that elastically urges the support in a direction in which the peeling claw or blade moves away from the heating roller; A fixing device comprising a freely openable and closable opening/closing member that presses down the support member against the biasing force of the spring elastic body.