JP2001022218A - Separation claw cleaner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a separation claw cleaner which securely cleans the entire separation claw with a single cleaning member and does not hinder removal of a jam. SOLUTION: A separation claw cleaner for cleaning a separation claw 4 which separates a transfer material P from a fixing roller 1 in contact with the surface of the fixing roller (rotary body) 1 comprises a cleaning member 18 movable in the direction of the rotary shaft of the fixing roller 1. The cleaning member 18 moves in contact with the separation claw 4 in the direction of the rotary shaft of the fixing roller 1, thereby cleaning the separation claw 4 while separating it from the fixing roller 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a separation claw cleaning device for cleaning a separation claw for separating a transfer material from a rotating body in an electrophotographic copying machine, a laser beam printer (LBP), or the like.

[0002]

2. Description of the Related Art Conventionally, as a fixing device in an image forming apparatus, a transfer material is passed between two rollers, and a roller in contact with a surface of the transfer material carrying a toner image is heated by a heater to generate heat. A type in which a toner image is fixed on a transfer material by pressure is known. In such a fixing device, a plurality of separation claws are provided in regular contact with the roller so that the transfer material does not wind around the roller after fixing, and the separation material is used to peel off the transfer material and discharge the transfer material.

Usually, the surface of a fixing roller is coated with Teflon (registered trademark) to prevent offset, and oil as a release agent is applied.

However, it is difficult to prevent the offset phenomenon that the toner adheres to the roller. If the offset toner is present on the roller surface, the tip of the separation claw that is in contact with the roller is stained with the offset toner, and the separation claw and the roller are caught. During this time, toner accumulates, and the separation performance of the transfer material by the separation claw is significantly reduced. For this reason, a device for cleaning the separation claw has been conventionally proposed (Japanese Utility Model Laid-Open No. 55-112259).
No., JP-A-1-125467, JP-A-2-58268
No., JP-A-2-81553).

[0005]

However, in the proposal described in, for example, Japanese Utility Model Laid-Open Publication No. 55-121259, since the separation claw and the cleaning member are integrally formed, the cost as the separation claw increases, and the separation claw is increased. There is a problem that the nail cannot be easily replaced.

[0006] The separation claw is originally a consumable, and it is desirable that the separation claw can be used as it is, which can be easily replaced and whose unit cost is low. When the separation claw cleaning member is attached, it is necessary to consider that the separation claw cleaning member is not damaged when a jam occurs or does not interfere with the jam clearance.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and a purpose thereof is to ensure that all the separation claws can be cleaned with a single cleaning member, and do not hinder jam processing. An object of the present invention is to provide a separation claw cleaning device.

[0008]

In order to achieve the above object, the invention according to claim 1 provides a separation claw cleaning device for cleaning a separation claw that contacts a surface of a rotating body and separates a transfer material from the rotating body. A cleaning member movable along a rotation axis direction of the rotating body, and the cleaning member moves while contacting the separation claw along the rotation axis direction of the rotating body to rotate the separation claw. It is characterized in that it is cleaned while being separated from the body.

According to a second aspect of the present invention, in the first aspect of the present invention, the cleaning member cleans the separation claw by moving in contact with the plurality of separation claws.

According to a third aspect of the present invention, in the first aspect of the present invention, the contact side of the cleaning member with which the separation claw contacts and the moving axis of the cleaning member moving along the rotation axis direction of the rotating body. The cleaning member is constituted by a sheet having an obtuse angle α.

According to a fourth aspect of the present invention, in the first aspect of the invention, a triangular wing is provided on an upper portion of the separation claw.

According to a fifth aspect of the present invention, in the first aspect of the present invention, the cleaning member is arranged at a home position outside a paper passing area in a longitudinal region of the rotating body during a non-cleaning operation.

According to a sixth aspect of the present invention, in the first aspect of the present invention, there is provided a driving means for automatically moving the cleaning member along a rotating body axial direction.

According to a seventh aspect of the present invention, in the first aspect of the present invention, the rotating body is constituted by a fixing roller.

According to an eighth aspect of the present invention, in the first aspect of the present invention, the cleaning operation of the separation claw by the cleaning member is performed at a certain temperature or more and up to a weight increase.

According to a ninth aspect of the present invention, in the first aspect, an image output number signal, an image output number signal weighted by the size and type of the transfer material, and an image output number weighted by image density information The cleaning operation of the separation claw by the cleaning member is performed by a signal or an image output number signal weighted by the ambient temperature and the standby time from when the main power is turned on.

[0017]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

<Embodiment 1> FIG. 1 is a sectional view of a fixing device provided with a separation claw cleaning device according to Embodiment 1 of the present invention, and FIG. 1A shows the separation claw in contact with a roller. FIG. 4B shows a state in which the tip of the separation claw is separated from the roller by the cleaning member.

In FIG. 1, reference numeral 1 denotes a fixing roller 1;
A heat source H such as a halogen heater is provided therein, and a pressure roller 2 is pressed against the fixing roller 1. Here, the fixing roller 1 is configured by coating a non-adhesive resin or rubber on a core metal such as aluminum, and is driven to rotate in a direction indicated by an arrow (clockwise) in the figure.

The pressure roller 2, which is pressed against the fixing roller 1, has a relatively thick coating layer made of an elastic material such as silicone rubber on the surface thereof. 1 and transported. Then, the unfixed toner image T on the transfer material P is heated and fixed on the transfer material P by the fixing roller 1.

A temperature sensing element 3 such as a thermistor is provided in contact with the outer peripheral surface of the fixing roller 1, and a detection signal of the temperature sensing element 3 is sent to a known temperature control means (not shown). The temperature of the outer peripheral surface of the fixing roller 1 is maintained at the toner melting temperature by the temperature control means.

Further, a separation claw 4 is in contact with the surface of the fixing roller 1, and the separation claw 4 adheres to the surface of the fixing roller 1 and is transferred around the fixing roller 1. The material P is separated from the fixing roller 1. The pressure roller 2
The separation claw 6 is also abutted.

Further, a web cleaning device 5 is disposed around the fixing roller 1 to remove offset toner on the surface of the fixing roller 1.

Here, the separating claw 4 is formed by coating a fluororesin such as PFA on a polyimide or polyamide resin, and the separating claw 6 is in contact with the pressure roller 2 at a lower temperature than the fixing roller 1. Inexpensive P with low heat resistance
It is constituted by coating a fluororesin on a PS or polyamide resin.

The separation claw 4 is rotatably supported around a rotation shaft 7, and its tip is in contact with the fixing roller 1 by a spring 8. Reference numeral 9 denotes a holder for the separation claw 4, which also functions as a paper guide. Similarly, the separation claw 6 is also rotatably supported around the rotation shaft 10, and its tip is in contact with the pressure roller 2 by a spring 11.

Next, a separation claw cleaning device according to the present invention will be described.

Reference numeral 18 denotes a cleaning member.
Is composed of a heat-resistant sheet such as a polyimide sheet.
7 is fixed by bonding. The sheet metal 17 is fixed to a block 15 having an H shape, and the block 15 can move the sheet metal 17 and the cleaning member 18 by a bar 16 in parallel with the axial direction of the fixing roller 1. or,
The H-shaped block 15 is fitted in a rail-shaped hole 14 formed in a stay 13 constituting a frame of the fixing device, and a bar 16 is moved in parallel to the fixing roller 1 from the front to the back. By moving, the block 15 and the cleaning member 18 can be moved from the near side to the far side.

Next, FIGS. 2A to 2D show the fixing device as viewed from the rear side of the separation claw 4 (in the direction of arrow A in FIG. 1).
However, in these figures, parts that are not necessary for description are partially omitted.

A pressure roller 2 is pressed against the fixing roller 1, and five separating claws 4 for separating the transfer material P are arranged at appropriate intervals in the axial direction of the fixing roller 1.
The cleaning member 18, the sheet metal 17 and the block 15 are connected to a bar 16, and when the bar 16 is pulled to the near side, the cleaning member 1
8 moves parallel to the axis of the fixing roller 1.

The block 15 is fitted in a rail-shaped hole 14 formed in the stay 13 and moves parallel to the fixing roller 1 along the hole 14. The cleaning member 18 is made of a highly heat-resistant polyimide sheet and has a triangular tip at the tip as shown in the figure.

FIG. 2A shows a state in which the cleaning member 18 is at the home position in the non-sheet passing area. FIG.
2A to 2D show a state in which the bar 16 is pulled in this order from the back to the front, and FIG. 2C shows a state in which the cleaning member 18 just pushes up the tip of the separation claw 4 and passes therethrough. Is shown. FIG. 1B shows the fixing device in this state as viewed from the cross-sectional direction.

FIG. 2 (d) shows that the cleaning member 18 is
FIG. 1A is a cross-sectional view of the fixing device in this state. As described above, the cleaning member 18 moves from the back in the longitudinal direction of the fixing roller 1 to the front or from the front to the back while pushing up the tip of the separation claw 4, so that the toner at the tip of the separation claw 4 is cleaned. In this case, since the tip of the cleaning member 18 has a triangular shape, the cleaning member 18 can advance in the longitudinal direction of the fixing roller 1 while pushing up the separation claw 4. The thickness of the cleaning member 18 is usually 100 to 500.
A polyimide sheet of about μm is used.

FIG. 3A shows the force f1 which the separating claw 4 receives from the cleaning member 18 when the cleaning member 18 moves in the direction of arrow B (the axial direction of the fixing roller 1) and comes into contact with the separating claw 4. I have. When this force f1 is divided, component forces fa, fb, f
c (see FIG. 3B), and the component force fb rotates the separation claw 4 about the rotation shaft 7 to separate the separation claw 4 from the fixing roller 1. At this time, the contact side L of the cleaning member 18 with the separation claw 4 in the direction of arrow B (the axial direction of the fixing roller 1).
Is large, the cleaning member 18 rotates the separation claw 4 smoothly. Moreover, since the width of the cleaning member 18 that crosses the tip of the separation claw 4 increases, the cleaning effect also increases.

However, since the width of the cleaning member 18 is large, there is a disadvantage that a large space is required.
When the angle α is large, a sheet having a considerably small thickness can be used as the cleaning member 18 without any problem. However, it is better to use a thick sheet as the width is reduced. Furthermore, the angle α
When the separation claw 4 is pushed up by using a thick sheet for the cleaning member 18, the possibility of damaging the tip of the separation claw 4 increases. Therefore, it is better to set the angle α to be larger than 120 °.

Second Embodiment Next, a second embodiment of the present invention will be described with reference to FIG.

In the first embodiment, a triangular sheet is used as the cleaning member 18. However, the present invention is not limited to this. It is also possible to use the sheet-shaped cleaning member described above.

That is, as shown in FIG.
Numeral 0 is formed by attaching a triangular wing 41 to the upper part of the conventional separation claw 4 used in the first embodiment. FIG.
4A, reference numeral 42 denotes a rotation shaft of the separation claw 40, reference numeral 43 denotes a locking groove for hooking a spring, and reference numeral 44 denotes a tip of the separation claw 40. FIG. 4B is a side view of the separation claw 40, and the triangular wings 41 are provided only above the separation claw 40 as illustrated. The wings 41 have a role to smoothly rotate the separation claw 40 when the cleaning member 18 pushes the separation claw 40 from the lateral direction (in a direction in which the separation claw 40 is separated from the fixing roller 1 and turned off). Rotate). Then, the cleaning member 18 passes by rubbing the tip 44 of the separation claw 40. The cleaning member 18 is separated from the front to the back of the page.
When 0 is pressed, the cleaning member 18 and the wing 41 slide, and the separation claw 40
Rotates in the direction of arrow C in FIG. At this time, if the wings 41 of the separation claw 40 form a triangle, the cleaning member 18
Even if the sides are not triangular, the cleaning member 18 moves smoothly. For this reason, a thin rectangular sheet can be used as the cleaning member 18.

Further, in the case of the present embodiment, the user and a service person reciprocate the bar 16 as necessary to clean the separation claw 40. here,
In order to clean all the separation claws 40, the bar 16 may be pulled until the cleaning member 18 comes to the front. The cleaning member 40 is located in the non-sheet-passing area at the back of the fixing device at the home position, so that even if a jam occurs, the cleaning member 18 is not damaged. Further, since the cleaning member 18 is attached to the stay 13 of the frame of the fixing device main body, there is no influence when the jam is cleared by opening and closing the claw unit supporting the separation claw 40 when a jam occurs.

Further, the user can clean the separation claw 40 without soiling his / her hands, and the jam occurrence rate in the fixing device has been greatly reduced.

Third Embodiment Next, a third embodiment of the present invention will be described with reference to FIGS.

In the first embodiment, the separating claw 4 is cleaned by manually pulling the rod 16 in order to keep the cost low. However, in the present embodiment, a motor is used instead of manually pulling the rod 16. I used it to drive.

FIG. 5 is a view of the separation claw viewed from the back, and FIG. 6 is a sectional view of the fixing device. In these figures, the same elements as those shown in FIGS. 1 and 2 are denoted by the same reference numerals. Hereinafter, the description thereof will be omitted.

In FIGS. 5 and 6, M is a motor capable of rotating forward and backward, and this motor M is controlled by a control signal. S denotes a screw rod, which is driven to rotate by a motor M. The rotation of the screw rod S causes the cleaning member 18 to move from the back to the front and from the front to the back in the longitudinal direction of the fixing roller 1. .

As shown in FIG. 7, a helical groove similar to the screw rod S is formed outside the screw rod S so that a holder member F formed inside the screw rod S covers a part of the screw rod S. Are located. The screw rod S and the holder member F have a so-called bolt-nut relationship,
The nut moves as the bolt rotates.
Since the cleaning member 18 is fixed to the holder member F, the rotation of the screw bar S moves the cleaning member 18 from the front to the back and from the back to the front.

K is a block for rotatably fixing the screw rod S to the stay 13, and this block K is disposed at the rear end and the front end (the front is not shown).

In the above configuration, the cleaning member 18 can be moved in the longitudinal direction of the fixing roller 1 by the rotation of the motor M.

Next, the operation timing of the cleaning member 18 will be described with reference to the flowchart shown in FIG.

First, the main switch of the copying machine is turned on (step S1), the heater H of the fixing device is turned on, and the temperature of the fixing roller 1 increases. And the fixing roller 1
Is detected (step S2), and it is determined whether or not the temperature is above a certain value (for example, 130 ° C.) (step S3). When the surface temperature of the fixing roller 1 exceeds a predetermined value (130 ° C.), the cleaning member 18 starts to move, and after the cleaning member 18 performs one reciprocation of the separation claw 4, the separation claw copy number counter is reset. (Step S4). Thereafter, it is determined whether or not the wait-up has been completed (step S5). The wait-up is performed until the surface temperature of the fixing roller 1 rises and the wait-up is completed (step S6). A copy operation is performed (step S7).

When one job is completed, it is determined whether or not the number of copies exceeds a certain value (2000) (step S8). If the number of copies exceeds 2,000, automatic cleaning is performed immediately after the job. Is started, and the cleaning operation of the separation claw 4 is performed one round trip (step S9).

As described above, immediately before the morning weight-up and 2
After copying 000 sheets, the separation claw 4 is automatically cleaned. By doing so, the separation claw 4 is cleaned while the toner is slightly warmed, so that the fixing roller 1 and the tip of the separation claw 4 are hardly damaged.

Further, since the cleaning is started before the wait-up temperature, there is an advantage that the wait time does not become long.

Further, the separation claw 4 is reliably cleaned because it is automatically cleaned every 2,000 sheets, and a great effect is obtained in preventing the fixing separation jam.

In this embodiment, the automatic cleaning of the separation claw is performed using the information of the number of copies as the automatic cleaning timing. However, the present invention is not limited to this. The timing may be determined.

Incidentally, first, the separation claw is easily stained when the toner offset amount to the fixing roller is large. Therefore,
The toner offset amount varies depending on the size of the paper. Therefore, the A3 size is counted as twice the A4 size. Alternatively, there is a method using a number weighted by the paper size.

For example, N = 2 × (A3 copy number) +
1.5 x (number of B4 copies) + 1 x (number of A4 copies)
+ 0.7 × (the number of B5 copies), and the value of N is 20
Weighting such as cleaning when the value exceeds 00 can be performed. It should be noted that the flowchart is not particularly described since it is sufficient to use this number N for the number of copies. Further, in the case of a web cleaning device, since the number of times (pulling amount) of the web is changed according to the size and the situation, there is a method of operating the separation claw cleaning device according to the web pulling amount.

Further, since the toner offset amount is affected by the image ratio and the environmental temperature and humidity, it may be changed based on such information. For example, when the environment sensor provided in the apparatus detects that the temperature is low, the number of copies is changed from 2000 at normal temperature to 1000 at normal temperature. Alternatively, a method may be considered in which the detection potentials of the potential sensors are integrated to detect the image ratio, and when the integrated value is equal to or greater than a certain value, the separation claw is cleaned.

In the first embodiment, an example in which a polyimide sheet is cut into a triangular shape as a cleaning member has been described. A sheet obtained by coating these rubbers) can also be used. By using the rubber member as the cleaning member, the cleaning member softly hits the separation claw, so that the tip of the separation claw is not damaged.

Further, it is also possible to make it difficult for the toner to adhere to the cleaning member by applying a polyimide coated with Teflon or a Teflon tape to the polyimide film and making the outside of the film a fluororesin. By doing so, the cleaning member is prevented from being stained, and the life thereof is extended.
Also, because the cleaning member has good sliding properties, it does not damage the separation claw,
The cleaning member can be moved smoothly.

In addition, a felt may be attached to the surface of the polyimide, and the felt may be impregnated with oil to form a cleaning member. By doing so, the cleaning power is increased as compared with a simple sheet member.

Although the above embodiment has been described with respect to the separation claw that comes into contact with the fixing roller of the fixing device, the present invention relates to another separation claw that separates the transfer material from the rotating body (for example, a separation claw attached to a photosensitive drum) The same can be applied to the nail).

[0061]

As is apparent from the above description, according to the present invention, there is provided a separation claw cleaning device for cleaning a separation claw which comes into contact with the surface of a rotating body to separate a transfer material from the rotating body. A cleaning member movable along the rotation axis direction of the rotation member, and the cleaning member moves while contacting the separation claw along the rotation axis direction of the rotation member to separate the separation claw from the rotation member. Since the cleaning is performed while cleaning, all the separation claws can be reliably cleaned with a single cleaning member, and an effect is obtained that the separation claw cleaning device does not hinder the jam processing.

[Brief description of the drawings]

FIG. 1 is a sectional view of a fixing device including a separation claw cleaning device according to Embodiment 1 of the present invention.

FIG. 2 is an explanatory diagram of the operation of the separation claw cleaning device according to the first embodiment of the present invention (a view in which the fixing device is viewed from the rear side of the separation claw).

FIG. 3 is a diagram illustrating a force that the separation claw receives from the cleaning member in the separation claw cleaning device according to the first embodiment of the present invention.

FIG. 4 is a configuration diagram of a separation claw according to Embodiment 2 of the present invention.

FIG. 5 is a diagram illustrating a separation claw cleaning device according to a third embodiment of the present invention (a view in which a fixing device is viewed from a rear side of a separation claw).

FIG. 6 is a sectional view of a fixing device including a separation claw cleaning device according to Embodiment 3 of the present invention.

FIG. 7 is a flowchart illustrating a control procedure of operation timing of a cleaning member in the separation claw cleaning device according to Embodiment 3 of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fixing roller (rotating body) 4, 6 Separation claw 16 Rod 18 Cleaning member 40 Separation claw 41 Wing M Motor (Drive means) P Transfer material S Screw rod (Drive means)

Claims (9)

[Claims] An apparatus for cleaning a separating claw that separates a transfer material from a rotating body by contacting a surface of the rotating body, comprising: a cleaning member movable along a rotation axis direction of the rotating body. A separation claw cleaning device, wherein a cleaning member is configured to move while being in contact with the separation claw along the rotation axis direction of the rotating body so as to clean the separation claw while separating the separation claw from the rotating body. 2. The separation claw cleaning device according to claim 1, wherein the cleaning member cleans the separation claw by moving in contact with the plurality of separation claws. 3. The cleaning member is constituted by a sheet having an obtuse angle α between a contact side of the cleaning member with which the separation claw contacts and a movement axis of the cleaning member moving along the rotation axis direction of the rotating body. The separation claw cleaning device according to claim 1, wherein: 4. The separation claw cleaning device according to claim 1, wherein a triangular wing is attached to an upper portion of the separation claw. 5. The separation claw cleaning device according to claim 1, wherein the cleaning member is arranged at a home position outside the paper passing area in a longitudinal region of the rotating body during a non-cleaning operation. 6. The separation claw cleaning device according to claim 1, further comprising a driving unit for automatically moving the cleaning member along the axis of the rotating body. 7. The separation claw cleaning device according to claim 1, wherein the rotating body is constituted by a fixing roller. 8. The separation claw cleaning apparatus according to claim 1, wherein the cleaning operation of the separation claw by the cleaning member is performed at a certain temperature or higher and until the weight increases. 9. An image output number signal, an image output number signal weighted by the size and type of a transfer material, an image output number signal weighted by image density information, or an ambient temperature and a standby time from a main power ON. 2. The separation claw cleaning device according to claim 1, wherein the cleaning member performs a cleaning operation of the separation claw by the weighted image output number signal.