JPH03172883A - Fixing device - Google Patents

Abstract

PURPOSE:To easily attach a cleaner to a fixing device main body by positioning the cleaner between a fixing roller and a 1st spring member and then turning the cleaner main body or a handle part so that a cam may be engaged with the 1st spring member in the case of attaching the cleaner to the fixing device main body. CONSTITUTION:At the time of attaching the new cleaner 20 to a cleaner mounting part 30, a pad part 21 is allowed to turn downward and the guide pin 24 of the cleaner main body 22 is engaged with the side groove 31 of the mounting part 30 and allowed to descend. When it descends to a specified position, the handle 23 is turned downward centering around the guide pin 24 so that the pad part 21 is allowed to abut on the surface of a heating roller 12 and the cam part 25 of the main body 22 is engaged with the pressing part 32a of a supporting spring 32 to make the main body 20 in a state where it is pressed to the roller 12, positioned and fixed by the spring 32. By performing an action reversely in such constitution, the cleaner 20 can be detached. Thus, the device is miniaturized and simplified.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a fixing device for an image forming apparatus such as a copying machine or a laser beam printer that employs an electrophotographic method.

(Prior Art) In an image forming apparatus such as a copying machine, when a toner image is transferred from an image carrier onto a transfer paper, the transfer paper is conveyed to a fixing device and the toner image is fixed as a permanent image on the transfer paper. be done.

To explain an example of the above fixing device using 1s8rA, reference numeral 100 in the figure is a heating roller that is provided with a heater and whose outer surface temperature is maintained at a predetermined fixing temperature, and the heating roller 100 includes a pressure roller. 101 is pressed. When the transfer paper P carrying the toner image is conveyed to the heating and pressure roller 100, which is a fixing roller that rotates in a constant direction, and the IOIM, the transfer paper P is heated and
The toner image is conveyed while being sandwiched between paper sheets 00 and 101, and the toner image is heated and melted and fixed on the transfer paper.

The heating roller 100 is also provided with a cleaner 110 in its axial direction, which cleans toner etc. that has adhered around the heating roller 100 during fixing work, and also applies oil such as silicone oil around the heating roller 100. This prevents toner from adhering to the heating roller 100.

The cleaner 110 is positioned in the hole 121 of the fixing device main body 120 so that its felt part 111 comes into contact with the heating roller 100, and then the spring member 132 The heating roller 100 is pressed down through the heating roller 100 .

On the other hand, this cleaner 110 generally only needs to be replaced every 3,000 to 4,000 sheets of transfer paper P to be fixed, and the frequency of replacement is low, and once it is installed in the fixing device, there is no opportunity to lift the fixing cover 130 and take out the cleaner 110. is small.

(9, Section 8 to be clearly solved) However, although the number of times the cleaner 110 is replaced is small, the mechanism for attaching and detaching the cleaner 110 is not simple.

That is, not only is the fixing cover 130 and the spring member 132 necessary, but the fixing cover 130 also requires a stopper (not shown) to prevent the fixing cover 130 from opening against the elastic force of the spring member 132. Therefore, the number of parts was large and there was a problem in terms of cost. Further, when the fixing cover 130 is opened to replace the cleaner 110, a sufficient gap is required between the cleaner 110 and the fixing cover 130 for attaching and detaching the cleaner 110, which causes the inconvenience of increasing the size of the apparatus.

Also, as in the fixing device shown in FIG.
or the spring member 132 in the upper unit 200 of the image forming apparatus.
In the case of a clamshell type device that is pressed through 200 is opened, the pressure of the cleaner 110 on the heating roller 100 is also released, so the heating and pressure rollers 100, 101f! If an unnecessary transfer paper P is pulled out from the Jf, the unfixed toner on the transfer paper P will adhere to the heating roller 100 without being sufficiently cleaned, which may cause the inconvenience of staining several subsequent transfer papers P. Ta.

The present invention has been made in view of the above-mentioned problems, and its purpose is to provide a fixing roller that allows the cleaner of the fixing roller to be attached and detached with a simple mechanism, and that can fully utilize the function of the cleaner even when dealing with jams, etc. We are in the process of providing equipment.

(Means for Solving the Problems) In order to achieve the above object, the present invention includes a cleaner that is detachably attached to the fixing device body and that is pressed against the fixing roller to clean the outer surface of the fixing roller. In the fixing device, a cam portion is formed on the cleaner body itself or a handle portion pivotally supported by the cleaner body, and a first spring member for suppressing the cleaner is fixed to the fuser body side, and the first spring member is fixed to the fuser body side. The present invention is characterized in that the cleaner positioned between the fuser roller and the fixing roller is attached to the fuser body by rotating the cleaner body or the handle portion to engage the cam portion with the spring member.

Further, the second invention provides a fixing device having a cleaner which is detachably attached to the fixing device body and which is pressed by the fixing roller to clean the outer surface of the fixing roller. A handle portion supported to be movable up and down is provided, and the handle portion is provided with a cam portion that presses the cleaner main body downward via a second spring member when the handle portion rotates, and the handle portion is locked to the fuser main body. In this state, the cleaner body is pressed against the fixing roller by rotation of the handle portion, and the cleaner is attached to the fixing device body.

(Function) In the first invention, when attaching the cleaner to the fixing device main body, after positioning the cleaner between the fixing roller and the first spring member, the cleaner main body or the handle portion is rotated to attach the cam portion to the first spring member. The cleaner was attached to the fuser body by engaging the cleaner. Incidentally, to remove the cleaner from the fixing device main body, it is sufficient to perform the operation in the opposite direction to that described in L.

In addition, in the second invention, in order to attach the cleaner to the fixing device main body, the cleaner main body is first placed on the fixing roller, and then the handle portion is stopped on the fixing device main body. After that, when the handle part is rotated and the cam part presses the fixing body downward via the second spring member, the cleaner body is pressed toward the fixing roller because it can move up and down with respect to the handle part. A cleaner can be attached to the fuser body.

Incidentally, the cleaner can be removed from the fixing device body by performing the operation opposite to the above.

(Example) Embodiments of the present invention will be described below based on the accompanying drawings.

First, a first embodiment of the present invention will be described with reference to FIGS. 1 and 2.

First, an outline of the image forming operation by an image forming apparatus such as a laser beam printer will be explained with reference to FIG. There is a primary charger 2. Developing device 3.
A transfer charger 4 and a cleaning device 5 are provided, and a fixing device 6 is provided on the paper discharge side of the photosensitive drum 1.

In other words, the photosensitive drum l uniformly charged by the charger 2
When image light is exposed from a scanner unit (not shown) or the like above, an electrostatic latent image is formed on the photosensitive tram l. The electrostatic latent image is directed toward the developing device 3 as the photosensitive tram 1 rotates, and toner is supplied by the developing device 3 and visualized as a toner image. The image is transferred onto transfer paper P.

On the other hand, the transfer paper P is conveyed toward the photosensitive tram 1 and the transfer charger 4 at the same timing from a paper feeding system (not shown), or the toner image on the photosensitive drum l is transferred via the transfer charger 4. Once transferred, the toner image is conveyed to the fixing device f16, where the toner image is fixed onto the transfer paper P as a permanent image. Further, the photosensitive drum after the transfer is cleaned of residual toner by a cleaning device 5 and is prepared for the next image formation.

Next, the fixing device 6 according to the present invention will be explained with reference to FIG. 1. Reference numerals 12 and 13 in FIG. It has a function. heating roller 1
2 is rotatably driven in the direction of the arrow shown in the figure, has a halogen heater 12a inside, and its outer surface temperature is heated to a constant fixing temperature, and a thermistor 14 is brought into contact with the upper side of the halogen heater 12a. The thermistor 14 detects the outer surface temperature of the heating roller 12 and the halogen heater 12
a is controlled.

Further, a pressure roller 13 disposed below the heating roller 12
is urged toward the heating roller 12 by a spring member (not shown), and is pressed against the heating roller 12.
A nip portion 19 is formed between the heating roller 12 and the heating roller 12 .

Furthermore, on the paper discharge side of the heating and pressure rollers 12 and 13, there is a separation claw 17 for separating the transfer paper P attached to the heating roller 12 via the toner image from the heating roller 12, and a separation claw 17 for separating the transfer paper P attached to the heating roller 12 via the toner image. A pair of carry-out rollers 15.16 for carrying out the paper P out of the fixing device 6, and an intermediate guide 18 that guides the transfer paper P carried out from the heating and pressure rollers 12 and 13 toward the pair of carry-out rollers 15.16 are arranged. The transfer paper P is heated on the paper feeding side of the heating and pressure rollers 12 and 13.

An inlet guide 11 is provided leading towards the nip 19 of the pressure rollers 12,13.

That is, when the transfer paper P carrying the toner image on its upper surface is conveyed toward the fixing device M6, the transfer paper P is guided by the input logite 11, heated, and heated at the nip portion 19 between the pressure rollers 12 and 13. The toner image on the transfer paper P is heated and melted by the pressure rollers 12 and 13, and is fixed on the transfer paper P as a permanent image. In this case, transfer paper P
is attached to the heating roller 12 via the toner image, or this transfer paper P is peeled off from the heating roller 12 by the separating claw 14, and transferred to the pair of delivery rollers 15 and 16 via the intermediate guide 19.
and is transported out of the fixing device 6 by the pair of transport rollers 15 and 16.

Now, if the heating roller 12 adheres to the toner on the transfer paper P or its outer surface during the fixing operation, the image on the transfer paper P will be disturbed, and in the next fixing operation, the attached toner will be transferred to the transfer paper P.
It has the disadvantage that it sticks to the top. For this purpose, the heating roller 12 is cleaned of toner adhering to the surface of the heating roller 12, and at the same time, oil such as silicone oil is applied to the surface of the heating roller 12 to reduce the adhesion of toner to the heating roller 12. A cleaner 20 is attached.

This cleaner 20 is arranged in the axial direction of the heating roller 12 and includes a butt part 21 that is pressed by the heating roller 12, a cleaner main body 22 that holds the bunt part 21, and an ax for the cleaner main body 22. Handle 2 fixed in a hook shape
3, etc., and is configured to be attached to and removed from the outer surface of the heating roller 12 from a cleaner attachment portion 30 on the upper right side in FIG. 1 of the fixing device main body IO.

Guide pins 24.24 having a circular cross section protrude from both ends in the axial direction of the heating roller 22 of the cleaner main body 22, and in the cleaner main body 22 near the guide pins 24.24, on the opposite side from the heating roller 22, a central guide pin 24. Cam part 2 with a chevron-shaped protruding part
5.25 is formed. In FIG. 1, only one side of the guide pin 24.24 and the cam portion 25.25 is shown. On the other hand, in the side wall 10a, loa of the fixing device main body IO forming the cleaner mounting portion 30, a side groove 3'l that engages with the guide pins 24, 24 of the cleaner 20 and guides the cleaner 20 toward the heating roller 12; 31 is formed. Further, the cleaner 20 is attached to the paper feed side front wall 10b of the fixing device main body lO on the lower side of the cleaner mounting section 30.
A support spring 32.32 for pressing the cleaner 20 is attached at a position facing the cam portion 25.25. The upper part of the support spring 32 is connected to the side groove 31 of the side wall 10a of the fixing device main body IO.
The tip of the pressing portion 32a is bent inward toward the cleaner mounting portion 30 in the shape of a (<).
The cleaner 20 is engaged with the cam portion 25 of the heating roller 1.
It has the function of pressing 2.

Therefore, when replacing the cleaner 20 of the fixing device 6 with a new one, the handle 23 in FIG.
The cleaner 20 can be removed from the cleaner mounting portion 30 by rotating the cleaner 20 upward around the guide pin 24, 24 and lifting the guide pin 24, 24 upward along the side groove 31, 31.

In this case, the pressing part 32a of the support spring 32.32.

32a is a cam portion 25 of the cleaner main body 22 as it rotates.
．． Since the cleaner 20 is pushed by the cleaner holder 25 and bent outward, the cleaner 20 can be easily removed from the cleaner mounting part 30.

Also, when attaching the new sag reach 20 to the cleaner mounting part 30, lower the guide pin 24.24 of the cleaner body 22 with the butt part 21 facing downward while engaging the side groove 31.31 of the cleaner mounting part 30. (In this case, the pressing part 32a of the support spring 32 may obstruct the lowering of the cleaner body 22, or the lower part of the cleaner body 22 may cause the support spring 32 to
Since the pressing portion 32a is pushed outward and the support spring 32 is bent outward, the cleaner main body 22 can be easily lowered. ), when the handle 23 is lowered to a predetermined position, if the handle 23 is rotated downward about the guide pin 24.24, the pad portion 21 will come into contact with the surface of the heating roller 12, and the cam portion 25. 25 engages with the pressing portions 32a, 32a of the support springs 32.32, and the cleaner main body 20 is pressed toward the heating roller 12 and fixed in position by the support springs 32.32.

As described above, the cleaner 20 has its guide pins 24 and 24.
The cam part 25.25 can be attached to and detached from the fuser body 10 by simply moving the cam part 25.25 along the side groove 31. Compared to conventional devices, the device can be made smaller, simpler, and lower in cost. Also cleaner 20
A large space is not required for attachment and detachment.

Next, a second embodiment of the present invention will be described with reference to FIG. Components having the same functions as those in the first embodiment are designated by the same reference numerals, and their explanations will be omitted.

In the fixing device 6 according to this embodiment, the cleaner mounting section 30 is provided on the upper side of the fixing device main body 10, and the thermistor 14 for detecting the temperature of the heating roller 12 is arranged at a position closer to the paper feeding side of the heating roller 12. It is set up.

Support protrusions 22a, 22a are formed at both ends of the cleaner main body 22 that holds the butt part 21, and the support protrusions 22a
, 22a, both ends of the horizontal portion 23a of the T-shaped handle 23 are pivotally supported by the holes 22a-1 and 22a-1 of the handle 23.

In addition, the cleaner body 22 is attached to the water outlet 23a of the handle 23.
A cam portion 25, 25 is formed toward the support protrusion 22a, 22a toward the grip portion 23b at the center of the handle 23. Further, the support springs 32 and 32 are provided at a position facing the cam portion 25 of the handle 23, and one end thereof is supported by the upper wall 10c of the fuser main body 10, and the other end is a free end and is used as a cleaner. It extends above the mounting part 30. The support spring 32, 32 has a pressing portion 3 that is slightly inclined downward toward the free end in a portion disposed above the cleaner mounting portion 30.
2a and 32a are formed.

Therefore, the grip part 23b of the handle 23 of the cleaner 20 is bent into a hook shape with respect to the cleaner main body 22, that is, in a horizontal state, and the cleaner 20 is positioned in the cleaner mounting part 30 of the fuser main body IO. . In this state, the butt portion 21 is in light contact with the surface of the heating roller 12. Next, attach the handle 23 to the cleaner main body 22, and
The grip portion 23b is rotated 90 degrees counterclockwise in the figure.
If the cam part 2 is in a vertical position as shown by the chain line,
5.25 is in an upward convex state and the support spring 32.32
It engages with the pressing parts 32a, 32a of. Thus, the support spring 32.32 is lifted slightly upward, or the cleaner body 22 is moved to the heating roller 1 via the support spring 32.32.
2 and is fixed.

Incidentally, in order to remove the cleaner 20 from the fixing device main body 10, it is sufficient to perform an operation completely opposite to the above.

As described above, in this embodiment as well, the cleaner 20 can be attached to and detached from the fixing device main body 10 using a small and simple mechanism, and the same effects as in the first embodiment can be obtained.

Next, a third embodiment of the present invention will be described with reference to FIGS. 4 and 5. Components having the same functions as those in the first and second embodiments are designated by the same reference numerals and their explanations will be omitted.

In this embodiment, the cleaner 20 includes a bat part 21, a cleaner body 22 having a pad part 21, and a T-shape that is rotatably supported by support protrusions 22a, 22a provided at both ends of the cleaner body 22. The hole 22a-1 that engages with the horizontal portion 23a of the handle 23 provided on the support protrusion 22a is a vertically oriented elongated hole. The outer end portions 23a-1, 23a-1 between the support protrusions 22a, 23a
It protrudes outward from 2a, and its cross section is approximately rectangular, with both sides of the circular shape being shaved off.

In addition, the handle horizontal portion 23 near the support protrusions 22a and 22a
A cam portion 25.25 is formed on the upper side of the cleaner body 22, and a U-shaped spring member is formed on the upper side of the cleaner body 22 to engage with the cam portion 25.25. 33°33 has been added.

On the other hand, a pair of cleaner guide plates 34 in which guide grooves 34a and locking grooves 34b for the cleaner 20 are formed are provided at both ends of the cleaner mounting portion 30 provided on the upper side of the fixing device main body IO. This guide groove 34a is formed to be slightly larger than the length of one side of the circular outer ends 23a-1, 23a-1 of the handle water section 23a of the cleaner 20, and the locking groove 34b is formed at the lower end of the guide groove 34a. It is provided in a circular shape that is slightly larger than the outer shape of the horizontal handle portion 23a.

Therefore, in order to attach the cleaner 20 to the cleaner mounting part 30 of the fuser main body IO, first, as shown in FIG. -1, 23a-1, the circular outer end 23a-1, 23a-1 of the handle horizontal portion 23a is attached to the cleaner guide plate 34°34.
The guide grooves 34a, 34a are engaged with the guide grooves 34a, 34a.
The cleaner 20 is lowered into the cleaner mounting part 30 along 34a.

When the butt part 21 is placed on the heating roller 12J:, the circular outer end 23a-1 of the handle horizontal part 23a
, 23a-1 is a cleaner guide plate.

34. The handle 23 is positioned in the locking position 1J34b, 34b of 34, and in this state, the handle 23 is rotated clockwise 9 in FIG.
When the handle horizontal part 23a is rotated 0 degrees, as shown by the chain line in FIG.
1, 23a-1 is locked in the locking grooves 34b, 34b, the handle 23 is also locked in the cleaner guide plate 34, 34.
It will be positioned and supported. In this case, as the handle 23 rotates, the cam portion 25.25 presses the cleaner body 22 downward via the spring member 33.33, so that the cleaner body 22 presses the hole 22a of the support projections 22a, 22a. -1, 22a-1, and the butt portion 21 is pressed against the heating roller 12.

As described above, in this embodiment as well, the cleaner 20 of the fixing device 6 can be attached to the fixing device main body lO with a simple mechanism, and the same effects as in the first embodiment can be obtained.

Further, as shown in FIGS. 6 and 7, a horizontal through hole 4 is formed in the handle horizontal portion 23a in a direction orthogonal to the handle portion 23b.
0, and a pin 4 with enlarged diameter at both ends inside the through hole 40.
1 is slidably provided, and the pin 41 and the handle horizontal portion 23
A spring member 42 is attached between the spring member 42 and the pin 4.
1, the same effect can be obtained by pressing the cleaner body 22 against the heating roller 12.

(Effects of the Invention) As is clear from the above description, according to the present invention, the cleaner can be attached to and detached from the fuser body using a simple structure consisting of a cam portion on the cleaner side and a first spring member on the fuser body side, and the device The cost can be reduced and the size can be reduced.

Further, according to the second invention, a rotatable handle portion having a cam portion is provided on the cleaner side, and a locking portion of the handle portion is provided on the fuser main body side, which is a simple structure. Since it can be attached and detached, the second invention can also achieve the same effects as the first invention.

Also number 1. According to the second aspect of the invention, the cleaner is pressed against the fixing roller regardless of whether or not the device clears a jam, so that the cleaner can sufficiently perform its function as a cleaner even when clearing a jam.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a fixing device according to a first embodiment, FIG. 2 is a diagram for explaining an overview of image forming work by an image forming apparatus, and FIG. 3 is a cross-sectional view of a fixing device according to a second embodiment. 4 is a sectional view of the fixing device according to the third embodiment, FIG. 5 is a state diagram of the fixing device in which the cleaner is about to be attached to the fixing device body, and FIG. 6 is the modification of the fixing device. FIG. 7 is a side view of the cleaner according to the example, FIG. 7 is a sectional view of the horizontal part of the handle of the cleaner according to the modified embodiment, and FIGS. 8 and 9 are diagrams for explaining the prior art. 6... Fixing device, lO... Fixing device body, 12...
Heating roller (fixing roller), 20...Cleaner, 22
. . . Cleaner main body, 23 . . . Handle portion (handle), 25 . . . Cam portion, 32 . . . Support spring (first spring member), 33 .

Claims (2)

[Claims] (1) It is removably installed in the fuser body, and
In a fixing device having a cleaner that is pressed by a fixing roller to clean the outer surface of the fixing roller, a cam portion is formed on the cleaner body itself or a handle portion pivotally supported on the cleaner body, and the cleaner is pressed against the fuser body side. fix the first spring member for the fuser, rotate the cleaner main body or the handle part to engage the cam part with the spring member, and move the cleaner to the fixer, which is positioned between the first spring member and the fixing roller. A fixing device characterized in that it is attached to a main body. (2) It is removably installed in the fuser body, and
In a fixing device having a cleaner that is pressed by a fixing roller and cleans the outer surface of the fixing roller, the cleaner body is provided with a handle portion that is rotatably and vertically movably supported, and the handle portion is provided with a handle portion that rotates to clean the outer surface of the fixing roller. A cam part is provided that presses the main body downward via a second spring member, and when the handle part is locked to the fuser main body, the cleaner main body is pressed against the fixing roller by rotation of the handle part, and the cleaner main body is pressed against the fixing roller. A fixing device characterized in that a fixing device is attached to a fixing device body.