JPS58200263A - Oil applicator for copier fixing device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fixing device for a photographing machine, and particularly to an oil application device thereof.

When a copy paper bearing a toner image is passed between a pair of rollers that are in pressure contact with each other and fixed, a portion of the toner adheres to the roller surface, which is the so-called offset phenomenon. Conventionally, it has been widely practiced to apply a suitable amount of anti-offset agent such as silicone oil to the surface of the roller.

As a typical means for applying this yuzu oil, for example, the one shown in FIG. 1A is known. That is, the fixing roller 1 is provided with a pressure roller 2 that presses against the fixing roller 1, and a toner image is formed between these rollers.
, 1+copy paper IJ i! In the case where fixing is carried out by passing through the copier, an applicator roller 6 is brought into contact with the fixing roller 1, silicone oil is stored in a container 4 placed at an appropriate location within the copying machine, and a felt 5 partially immersed in eye oil is placed.
is brought into contact with the applicator roller 6 with a substantially constant force, and the oil in the container is supplied to the fixing roller 1 via the felt 4 and the applicator roller 6 using capillary action.

In such a coating means, when the oil on the coating surface of the fixing roller 1 becomes insufficient and the frictional force between the roller 1 and the roller 6 becomes large, the coating roller 3 rotates and the oil is applied to the fixing roller 1.
If the amount of oil on the surface of the fixing roller 1 becomes too large, the applicator roller 3 will not follow the fixing roller 1 and the supply of oil will be stopped, and in this way, a constant supply of oil will be supplied to the fixing roller 1. It is now possible to do so. Since this type of paper utilizes the frictional force between the fixing roller and the applicator roller, and the change in force between the applicator roller and the felt material, especially if only narrow width copy paper is passed through,
Even though the oil in the part of the fixing roller corresponding to the copy paper is consumed, the relationship between the above-mentioned two friction forces does not change, and as a result, the applicator roller 6 rotates too much, so the fixing roller The problem of insufficient supply of oil to 1-l--which deteriorates the image quality of copies, could not be eliminated.

Such a drawback? In order to solve this problem, we have already developed JP-A IIs
No. 53-119053 Public ¥1 Special Enclosure 1982-6824
Oil application means as shown in Japanese Patent No. 0 and others have been proposed. FIG. 1B is an abbreviation of the information published in the above-mentioned official gazettes of both ministries.
Two sets of application rollers as shown in the sign roller 1 and 62 and 66 are arranged, and the oblique shafts are rotatable independently. Therefore, for example, it corresponds to the application roller 61 [1]
If the fixing process is performed on a copy paper, only the application roller 31 rotates to supply oil as the oil is consumed, so that the above-mentioned inconvenience caused by the movement of lJ of the copy paper does not occur. Figure 1'(!il', iii) shows the oil coating device listed in the Ministry's bulletin, which includes a fixing roller 1, coating roller 6, oil container 4, oil The guiding felt 5 and the like are basically the same as those shown in FIG. ), at least one of them is connected to a plunger 6, and by controlling the plunger 6, a part of the felt connected to it can be pulled off from the applicator roller, thereby controlling the oil supply range. It is constructed to fit into copy paper.

However, the known oil application device 1t described above
For devices such as those in which oil is constantly supplied to the fixing roller using capillary action, oil characteristics change depending on the surface condition of each roller and temperature and humidity.
In fact, it has been extremely difficult to constantly supply an optimum amount of oil to a predetermined location. If the fixing device is left in a stopped state for a long period of time, there is a risk that the applied oil will flow down from the applying roller to the fixing roller and stain the copy at the beginning of the next operation. This method has a crude structure and requires extra space within the copying machine, which poses problems in terms of cost and maintenance.

The present invention has been made in view of the above-mentioned current situation, and it is possible to quickly supply the surface of the fixing roller from a container containing silicone oil to a large number of thin oil supply tubes extending along the entire length of the roller in the axial direction. In addition, due to the characteristics of the oil itself, the oil is completely supplied to the fixing roller when no fixing work is being performed, and the oil is supplied only when necessary, and the above-mentioned large number of third-stage rollers are selectively operated. It is an object of the present invention to provide an oil applicator configured so that oil can be supplied only to a desired portion of the surface of a fixing roller.

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

2 and 3 A1B are a perspective view of the oil applicator of the fixing device according to the present invention and an enlarged cross-sectional view of the thin tube section showing the part from which oil is discharged, and in FIG. It is assumed that an oil storage container 6-4 is disposed at a suitable position above the fixing roller 1 which is in pressure contact with the roller, and the photographic paper P carrying a toner image advances in the direction of arrow A in the figure.

Container 4 containing anti-offset agent such as silicone oil
At the bottom of the fixing roller 1, the cross section is (tY
An L-shaped oil feeding member 41 is disposed, one end of which is attached to the bottom of the container, and the other end extending into a suitable position near the surface of the roller 21. A large number of thin tubes 7 are arranged in the oil feeding member 41 along the direction of its L-shaped cross section, and one end of each thin tube opens into the container 4.
The other end is open to the end of the fixing roller 1111 of the oil feeding member 41. A piezoelectric element 8 is installed near the open end of each thin tube located near the surface of the fixing roller, as shown in the enlarged cross section of FIG. 3A.

The oil in the container 4 flows through the thin tube Z due to gravity and capillary action.
The dimensions of each part are determined so that the oil enters the inside and reaches the opening end on the cline roller side, but due to the surface tension of the oil, it will easily flow out of the tube a if left in this state. Therefore, the inside of each a-neck is always filled with oil, and this oil is maintained in a stationary state.

When the copying machine is operated, when a predetermined voltage is applied to the valley piezoelectric element 8 by a cooling means (not shown) each time copy paper is fed, the piezoelectric element changes to the state shown in FIG. 5B due to the piezo effect. As shown in the deformation 17, the oil existing in this vicinity is 111ii'IN and the oil of constant 1 [1 is discharged from the open end. 1-11 As shown in FIG. 2, the released oil is contained and contained in the application part H9 made of an appropriate porous material such as felt or urethane foam made of foamed bubbles, which is attached to the fixing roller 1. After being distributed in one plant, it is uniformly supplied over the entire surface length of the W softening roller.

On the other hand, if the application of voltage is stopped, the piezoelectric element becomes obsolete, and the oil of the instep corresponding to the discharged oil is supplied from the W plate to the thin tube, returning to the stationary state shown in FIG. 3A.

To change the amount of oil supplied to the fixing roll h", it is sufficient to change the number of times the +E'tw voltage is applied to the element 8 for each sheet feeding.
It is also possible to control the oil supply amount by changing the inner diameter of the 1ill tube with a concave circle or by changing the size of the piezoelectric element.

In addition, by making it possible to apply voltage independently to the piezoelectric elements of each thin tube, or by dividing the thin tubes into multiple groups and making it possible to selectively apply voltage to the piezoelectric elements for each group, it is possible to Depending on the size of the fixing roller, it is possible to supply sufficient oil only to the necessary portions of the fixing roller.

As explained above, the oil application device according to the present invention has a large number of thin tubes arranged in a row in the 1111 m direction facing the fixing roller, and forcibly and continuously discharges oil by deforming the piezoelectric elements arranged in these thin tubes. Since it is 1iXtL, no oil is wasted to the fixing roller when the fixing device is not in use, and the amount of oil discharged by one voltage application to the piezoelectric element is constant, so the optimal amount of oil is always supplied. Since the oil can be stably supplied to the fixing roller, the offset phenomenon can be effectively prevented, and there is no risk that the copy paper will be soiled by oil.

In addition, since the operation of the thin tube can be easily and selectively controlled, sufficient oil can be supplied only to the required fixing roller surface, even for different types of copy paper. Coupled with the continuous configuration, oil can be used effectively without waste.

In the embodiment shown in No. 21 above, the applicator part 9 is interposed between the open end of the #I pipe 7 and the fixing roller 1, but depending on the number of Al1 pipes and the state of oil discharge. By interposing the coating 111X material, the discharged oil can also be directly supplied to the surface of the fixed roller.

In addition, a plate-shaped coating member extending in the 11111i1 direction of the fixing roller is arranged between one end of the thin blue opening and the surface of the fixing roller, and a large number of minute irregularities are formed on the surface of this plate-shaped coating member as necessary. -1N411 'The oil discharged from the tlt is dispersed as soon as it reaches the surface of the fixing roll.
It is also possible to construct the surface so that it is distributed as evenly as possible over all floors.

4 and 5A1 and 5B show another embodiment of the present invention. In this embodiment, the applicator 9, which is placed in contact with the fixed roller 1, is - A number of thin tubes 7 are arranged close to each other in the lower corner of one of the oil storage containers 4 and have one end opening into the container 4 and the other end opening near the application member 9, as in the previous embodiment. The foot monitoring rollers are arranged in rows over almost the entire length in the @ line direction. As is clear from the drawing, these thin tubes are held between a support part which is a part of the bottom wall of the container and a support member 42 which is placed in contact with the upper part of the thin tube 7. Furthermore, as can be seen particularly from FIGS. 5A and 5B, a concave notch 43 is formed at the outer end of the support member 42 and at the upper part of the open end of the thin tube 7, and this part has a concave notch 43 corresponding to each =W. A piezoelectric element 8 is arranged in each case.

As in the previous example, the container and
The oil in 4. is filled up to the open end of the thin tube 7, and the oil in the 5th
The oil is stationary in the state shown in Figure A. P)T
At a certain point in time, a voltage is applied to the piezoelectric element 8 to deform it. As a result, the narrow □ tube 7 is also deformed in the direction of narrowing its open end, and at this time, a certain amount of oil is discharged and supplied to the surface of the fixing roller 1 via the application member 9.

11- In this case as well, it is possible to remove the applicator part 9 and supply oil directly to the fixing roller 1, or to use a guide member for oil dispersion, as in the case of the above-mentioned embodiment. be.

[Brief explanation of the drawing]

FIG. 1A, +3 and C are explanatory drawings showing a known oil application means.FIG. 2 is a perspective view showing an oil application device according to the present invention.FIG. 6A and B are the open ends of the thin tubes shown in FIG. Fig. 4 is an enlarged sectional view showing the structure and operation of the invention, and Fig. 5 is a side view showing other embodiments of the present invention.
: and B are enlarged sectional views showing the structure and function of the open end of the thin tube shown in FIG. 4. DESCRIPTION OF SYMBOLS 1... Fixing roller, 2... Pressure roller, 6... Application roller, 4... Container, 5... Felt, 7... Thin tube, 8... 1 element of cloth, 9...・Coating member, 41...
Oil feeding member, 42...Support part 1114 figure

Claims (5)

[Claims] (1) Copy paper carrying a toner image is passed through and fixed between a pair of rollers that are in pressure contact with each other, and an offset phenomenon occurs in one roller of the pair of rollers that is in contact with a toner image. In the fixing device, the oil supply means includes an oil storage container and a plurality of thin tubes that guide the oil in the container to the vicinity of the roller surface on the side that contacts the toner image. , means for selectively discharging and blocking oil within the thin tube, the means being located near the opening end of the thin tube on the roller side. (2) The oil application device according to claim 1, which uses a piezoelectric element as a means for discharging and blocking oil in the thin tube. (3) The oil applicator according to claim 1, wherein the plurality of thin tubes can be individually drained and blocked from oil. (4) Claim 2 in which the piezoelectric element is arranged inside the thin tube
Oil applicator as described in section. (5) Claim 2 in which the piezoelectric element is arranged outside the thin tube
Oil applicator as described in section.