JPS5835570A - Image forming device - Google Patents

Abstract

PURPOSE:To use an efficient cleaning means more economically, by changing the linear speed of the movement of the cleaning means provided on a member, which can be brought into contact with an unfixed image, in accordance with changes of variable image forming conditions. CONSTITUTION:In accordance with changes of variable image forming conditions such as the change of the process speed for the copy of variable magnification of expansion, reduction, etc., the image density of an original, or the like, the linear speed of the movement of a cleaning means provided on a member which can be brought into contact with an unfixed image is changed. For example, a cleaning web 20 mounted on a shaft 201 under the state of a shape like a roll is pressed against the surface of a fixing roller 11 by a pressing roller 22 and is wound up around a take-up shaft 21. The speed of revolution of this take-up shaft 21 is changed by moving gears 26 and 27 through a plunger 29 by a magnification converting means 30.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image forming apparatus in which a printed image supporting material carries an unfixed image, and then the unfixed image is fixed on the image supporting material). Small variable magnification; detects unfixed image density on the photoreceptor dome surface or image support material in image forming apparatuses or companies whose booth speed is variable, such as by scanning the image of the original at once. Possible picture 11
The present invention relates to an image forming apparatus, such as an I-forming apparatus, which has means that can change the image forming conditions necessary for image formation.

Conventionally, in an electrophotographic image recording apparatus, the fixing device O cleaning method using a cleaning web does not change depending on the process speed or image density, but under the worst conditions for cleaning (when the process speed is high). In order to make it possible to clean even if the copy is close to a blank surface, or if there is a lot of offset O, etc., the cleaning web can be pressed and fed〉shield R41.
IiI&determined.

Therefore, when the amount of toner on the image support is small, or when the process speed is slow, fixing is sufficient, and the amount of offset is small, the cleaning capacity may run out and the printer may be used more than necessary. The problem was that the cleaning web was wasted and the cleaning web was wasted.

However, since the cleaning/web O replacement interval is delayed, under the worst conditions, the cleaning capacity may be exceeded, which is unavoidable. There are 6 cases in which there are 9 disadvantages, such as 9. 90 Here, I would like to supplement the explanation of 06-, why it is necessary to change the process speed (depending on the image density, etc.) in variable-magnification copying.

Normally, when changing the magnification, especially when making a reduction copy, it is necessary to form an image on the photoconductor at the same speed as when copying the original document of the size to be reduced. In order to obtain the same amount of exposure as when making a full-size copy, the exposure must be increased to compensate for the increased speed of latent image formation. Finally, the original manuscript is A3 size (420X297)
If you reduce an image to A4 size (297 x 210) by K, the long side will be multiplied by a (in this case, aζ0.7). , increase the brightness of the document illumination lamp by 14 times (approximately 1.
3 times), and it is necessary to increase the moving speed of the optical system components by a factor of 3. However, in order to move the optical system members stably and in good condition, there is naturally a limit speed (To), so it becomes necessary to consider other means than changing this moving speed. Furthermore, due to energy saving and electricity regulations,
There is also a need to consider countermeasures to limit the amount of power that can be supplied to devices.

Therefore, 90 can be considered.Instead of increasing the moving speed of the optical system, if you multiply the photoreceptor 0 moving speed by a, the number of copies per time will decrease, but the speed of the optical system will decrease. The idea is that it would be possible to create a latent image potential on the photoreceptor under the same conditions as a normal magnification without having to open the photoreceptor or increase the amount of light.

machining, energy saving, and power regulations (for example, 10/V1
Model that matches 5mm O power outlet F) K Yoshi outside S * Mound middle 1
Furthermore, the amount of toner on paper O.

It is often difficult to supply the necessary energy to maintain the necessary temperature to the heat source of the heat fixing device using 0W paper. Also, various problems such as those mentioned above can be speeded up.

This is because the probability of occurrence is increasing as the number of functions increases.

Therefore, it is an object of the present invention to solve the above-mentioned disadvantages, and to use an efficient cleaning means more economically. This image forming apparatus is characterized in that the moving linear velocity of leaning means, which is provided on a member that can come into contact with an unfixed image and is movable, is changed in response to changes in image forming conditions.

The present invention will be described in detail below with reference to the drawings. FIG. 1 is for explaining the main process of forming an oil image in an electrophotographic apparatus which is one of the image forming apparatuses for carrying out the present invention. This is a diagram. 1 is a fixing section, and 11 is a fixing row. 11 are in pressure contact with each other at a pressure ratio of -2.

17 is a photosensitive drum; 12 is a circular plate charger installed in the image forming department; 7S is disposed close to the photosensitive drum 17;
Reference numeral 12 denotes a guide member disposed close to the fixing row 2, and is made of a material that is charged to a polarity opposite to the charge 4 of the unfixed image 60 due to frictional charging with the support material 3 at both ends such as paper.

As is well known, the photosensitive drum 17 receives a copy signal, rotates in the direction of the arrow, and is pre-discharged by the pre-discharge charger 7 .

Next, the photosensitive drum 17 is charged by a primary charger 18), then subjected to secondary charge removal by a secondary charger 9, simultaneously subjected to a partial exposure to light, and then fully exposed to a cytram 1.
7, when the *'m potential of the lN image area is positive, a positive latent image is formed. Of course, it is also possible to employ other latent image forming methods 1, such as the Carlson process. This l
The image I am currently g1s is visible 1f1 in the current femto
becomes. In this one-field method, for example, -component magnetic peak edge (magnetic toner) 14! Rotating sleeve 10 while standing the ears with the weight of the net roller lO. conveyed by the drum 17
9'
10. A method of flying adhesion from the side can be used.O Of course, other developing methods can also be used.In any case, if the surface potential of the image area is positive as described above, the toner constituting the developer will be negative. It is a charged object. The paper 3 passes over the guide plate 17 and approaches the drum 17 and contacts the drum 17 to receive its visible image. The back side of the paper 30 is charged with a polarity opposite to that of the toner by the transfer charge 612, and after being transferred to the paper 3, it is electrically carried on the paper 3 as an unfixed image 6. After this, the photosensitive drum 17 is
The surface is cleaned (by row 216) in preparation for the next copy.

On the other hand, the paper 3 carrying the unfixed image fa6 is transferred to the internal member 2 in the direction of the arrow by the row 213 rotating in the direction of the arrow. As the paper 3 slides on the guide member 2, the charge 4 of the toner in the box that comes into contact with the guide member 20 paper 3
Because it is charged with the opposite polarity, that is, positive polarity, the 1lii image is
It is attracted to the paper 3 and is stably supported on the paper in good condition without being disturbed by other obstacles, and the I-RA vs. 1st1sK and paper S(
Considering the fixing part 1 in more detail, it is 4-2 which has a silicone rubber O elastic layer on a stainless steel pipe-shaped core metal. 2) Part of the toner surface is coated with a non-adhesive material such as rubber, but since the offset phenomenon cannot be completely prevented, a tarnishing method is necessary. come. Therefore, in general, as a means for such fixing and cleaning, (l) further separation is used.
To apply i*, (2) to cause pressure loss on the bat, (to press 4-2, which has poor lid releasability than the metal roller or fixing roller 2, and (4) to clean it with a cleaning blade), ( i) Various means such as cleaning with a cleaning blade are provided to improve the fixing performance.◎As shown in FIG. However, as machines have become faster and more multifunctional, for example, as in the case of this paper, SO sheets per minute (Mu4t is paper), 100V, 15
In the case of an image forming apparatus that has a reduction function in the image forming apparatus, due to the problems of the movement of optical system members such as mirrors and lenses, and the power supply capacity of the original illumination system as described above, it is difficult to make a reduction copy or to reduce the image density. If the fixing speed is insufficient, the process speed may be changed due to reasons such as insufficient supply of fixing sO. In this embodiment, when making a full-size copy, the process speed is reduced by 3 sO. On the other hand, when performing reduction copying from M size S to M4 size or from M3 size to B4 size, the process speed should be reduced to 241 m/a-ex.

As with Toshirogahi, the other conditions will also change depending on the change in condition O. Sebe; Like Biichi, Pua Ryu Su Speed 3
If the speed is as fast as 50/sec, the cleaning web aSS speed is moved at 5/min to obtain a sufficient leader effect.In contrast, the reduction copy is temporarily reduced, that is, the reduced boot speed is 24s/min. Well,
The following differences occur: 0, that is, the fixing device
In order to fuse to A, the amount of heat applied (unit time) and the pressure applied are increased, so that the fixing performance is improved. Therefore, if the cleaning web is moved at the same speed as when copying at the same size, if the cleaning web has more than enough IIe power in the tarrying queue, it will move IK, so it is a waste of resources and IO. Since the maintenance period is shortened, the service boost is improved more than necessary.The cleaning web can be cleaned with just a slight movement.The cleaning effect is maintained for a long time. I can do it with tkh and so ζ, and I'm going to have a pro dragon susubido $ 241 town- and a low-ranking turtle, and I'm going to have a good time with this example, and I'm going to have a good time!・Quetsupu O roll) After reducing the feed by 50X for 1-7 minutes, a large amount of leaning web O loss will be caused, and the above-mentioned method will be greatly prevented. S■／
Similarly to the minute O II movement speed, the leaning effect can be obtained by % enough for the tB-/minute O position, and the power consumption of rounding that gives a change in the movement speed of 5 ■/minute O is also small, but s
Since only a movement amount of 2-5wm1 minute is required, it is possible to save about half or less KTh''Ii.

The second figure shows the above-mentioned cleaning web placed in the fixing device. 20 is the cleaning web, which is first attached to the shaft in a single-shaped state. Wrap one end and collect the unnecessary part of the web. Use the roller to turn the heat source 11 on and press the 1sK block, and use the O pressure contact to offset the toner. In this implementation, the cleaning web O speed change is given as described in 1.
&-, gear 27 (-town) and gear 26 (number of teeth q) are supported rotatably by a support shaft 28 km 1.
This method uses two plungers to move the cylinder. 2
3 is a gear attached to the winding shaft 21, 25 is a transmission gear that transmits the drive from the motor 24, and both are supported by bearings so that they can rotate at a constant rate. These gears 23, 25° 21,! 7e The arrangement relationship is gear when moving the web 2o at low speed! 31.25
When the web 2o is moved at high speed 1 m-8 so that the gear 26 engages them in the middle, the gear 23.
7 is arranged in the middle so as to engage with both of them.

Now, in the 1 predetermined O magnification image forming process, the gear 26
The drive is transmitted to gear 23, and speed 1! When a speed corresponding to 20 is applied to the cylinder 20 to change its magnification to the 0th order, and a signal from the circle is seen from the magnification conversion means 3° to the plunger 29,
Support shaft 21asl! Move to the left, and gear 27 is gear! ＄, 28 is engaged and its movement is stopped at the 9th point.The two gears are adapted to the change magnification and the two companion gears transmit the drive. .

If the number of teeth Q of the gear 26 is set to 10, which is also smaller than the gear 2torm number P, then it can be said to be the above-mentioned O movement expansion, expansion mode conversion, and conversely, if *lkQ is larger than the number of teeth P, it is a reduction mode. It can be used for conversion. For example, if the number of teeth is set to P:Qxlonia in the reduction mode, a speed reduction of 3ON can be achieved.

The advantages of reduction have nine effects as described above, but the advantage of increasing the enlargement copy speed in enlargement mode is that even if the copy speed is increased, the cleaning effect can be sufficiently maintained without losing it. It is possible to make high- and long-distance copying possible, to improve all speeds (process speeds) as much as possible, and to achieve great advances in image formation. .

Of course, in image forming apparatuses including full-size, enlarged, and S-small image forming apparatuses, it is possible to achieve a more efficient cleaning effect by providing a degree of obstruction to the movement of the cleaning web according to the speed of each image forming apparatus, as described above. It is possible to give nine unique effects depending on each magnification mode.

When the position of the optical system moves to the position at the time of change, the signal for converting the feed speed is not only applied to the lens, but also to the fixing unit 11). Even when the cleaning capacity is low, the process speed may be lowered to improve the fixing performance, and the feed mode may be changed accordingly.Furthermore, the more the image exceeds the cleaning capacity, the more off-setting occurs in the fixing process. In the case of Yokame, Pro 7th Speed Hirooka -
You can increase the web feed speed by yourself. To do this, press both photoconductors 17 as shown in the figure.
Place the optics and accuracy tester 31.32 in the vicinity of the
lt2WJt) can change the query encounter. By placing the rollers at several places in the axial direction of the photoreceptor 170, and controlling them in accordance with the average maximum output of the detection signal O, it is possible to control the output more accurately. An example of the Omagaku sensor 31,
The position 32 is a preferred embodiment even if it is in the middle of the conveyance path such as the conveyor belt 15 as shown in FIG.

Also, place the document on the document table and change the developing bias or exposure amount depending on the density of the image. Although it is known to image I@ on a photoreceptor, the signal for changing the web speed may be coupled to a means for changing the polishing bias or exposure dose. Tsut
〉When the standard developing bias is 200 volts, when trying to take a dark original, the developing bias should be set to 500 volts)
K@) If there is a main body that has a means to change it, it is 1! , the current bias may be changed to 500 volts and the web feed speed may be increased at the same time.
If we can move the leaning means, change the process speed, change the exposure amount, change the fixing temperature, change the development bias, and do not change the image formation. %A By changing various conditions,
Fixation effect-2 When installed on medium pressure *w-tb or company-specific carriers, etc., the clean-endering effect of the cryo-product means is lost to the pressure, and the leaning effect is exerted for a sufficient amount of time. The above problems can be solved by providing an appropriate moving speed of the cleaning means according to each changing condition.The present invention is not limited to the above-mentioned embodiments. , III Claims 1! %O including all of the items listed in 1!

[Brief explanation of drawings]

* II a s To which the present invention is applied - Explanatory diagram of an image forming apparatus, 2nd m. Description of an embodiment of the present invention - 1. Figure 3. Another perspective view of an embodiment of the present invention, 4th - Morimoto This is a side view of another embodiment of the invention. l is the electrodeposition section, LAD fixing roller 11 line pressure 1-ra, 3rd company image support material 5 is pre-static charging II, 8th company - charger 9 is secondary charging, 10th company developer 17 is photoreceptor, 20 is clear 12 NOWETSU ZL is a winding shaft and a pressing roller made by 22 companies! 3.2B,! 6
．． ! 7 is gear 28 company support shaft 2 company plunger
30 is the applicant for the variable power conversion method, Canon Co., Ltd. agent, Gi Marushima - Schiff Raku - ik! ”1

Claims (1)

[Claims] Image forming device! ! In response to changes in variable image forming conditions,
tff! There is also an image forming device characterized in that the moving linear speed of the leaning means is changed by being moved by a member that can come into contact with the moving means.