JPS61233762A - Image recording device - Google Patents

Abstract

PURPOSE:To prevent toner form being melt-stuck on an intermediate recording medium and to prevent the intermediate recording medium from deteriorating in durability by transferring an unnecessary developer on the intermediate recording medium to a transfer roller temporarily and removing it from the transfer roller. CONSTITUTION:The cleaning blade 31 of a cleaner is fixed while clamped between sheet metal members 32 and 33; the sheet metal member 33 is rotatable around a pin 35 as shown by an arrow A to and from a rocking member 34, which is rotatable on a main device as shown by an arrow B to press the cleaning blade 31 at any time with uniform press-contacting force uniformly in the lengthwise direction of the transfer roller 9. If a defect in conveyance, etc., occur in a transfer roller 9. If a defect in conveyance, etc., occur in a transfer material to stop the operation of the device and the device is operated again while untransferred toner sticks on the drum 1 as the intermediate recording medium, almost all of the remaining toner on the surface of the drum 1 is offset to the transfer roller 9. Consequently, a cleaning means need not be operated for the drum 1 specially and the surface of the drum is prevented from deteriorating in durability.

Description

TECHNICAL FIELD The present invention relates to an image recording apparatus that forms an image on an intermediate recording medium, transfers this image to a transfer material, and records the image on the transfer material.

BACKGROUND ART Traditionally, this type of image recording has been carried out in electrophotographic copying machines and the like.Generally, a toner image formed on a photoreceptor drum, which is an intermediate recording medium, is transferred to a transfer paper or the like using a corona charger or the like. After the toner image is transferred onto the transfer material, the toner image is passed through a fixing device 7 to fix the toner image on the transfer material and output it.

As described above, in the past, the transfer and fixing of an image onto a transfer material were performed using separate devices, but an image recording device that performs transfer and fixing at the same time has previously been proposed.

This image recording apparatus uses a drum having a dielectric layer on its surface as an intermediate recording medium L7, forms an electrostatic latent image on the surface of the drum according to an image information signal, and uses a toner developer to form an electrostatic latent image on the surface of the drum. Visualize it into a toner image*! A transfer material is brought into contact with the toner image by a transfer roller, and the toner image is transferred from the tram surface onto the transfer material by pressure, and at the same time, the toner image is fixed onto the transfer material by the pressure.

This method of simultaneously performing transfer and fixing is extremely effective in that it simplifies the process, improves the reliability of the apparatus, and allows the apparatus to be made smaller.

This type of apparatus is provided with a cleaning means for cleaning the surface of the intermediate recording medium after it has passed the image transfer position. Examples of this cleaning means include a cleaning blade method in which a plate-shaped blade member made of a blade, metal, or rubber is brought into contact with the surface of the intermediate recording medium, and the residual toner adhering to the intermediate recording medium is scraped off by this blade member; , a polishing roller method in which a roller mixed with an abrasive is pressed against the surface of the intermediate recording medium, and the medium surface is polished little by little for cleaning; A web cleaning method in which the material is applied and polished is used.

However, if the device is used for a long time using the above cleaning method, the blades and rollers may become damaged.

When the contact pressure on an intermediate recording medium such as a web is large, the surface of the intermediate recording medium is gradually scraped away by the cleaner, the intermediate recording medium surface is worn out, and the dielectric properties of the surface change. There was a problem.

As a result, there were disadvantages in that the image deteriorated L7 and the durability of the intermediate recording medium decreased.

By the way, if the image recording device described above has very high transfer efficiency, as long as the device is operating normally,
Almost no cleaning means are required. Therefore, in order to avoid the above-mentioned drawbacks, it is conceivable that an image recording apparatus with good transfer efficiency be configured without a cleaning means, but if an abnormality in the apparatus, such as a transfer material failure, occurs, the following steps should be taken. Problems like this occur.

That is, if a transport failure of the transfer material occurs before or during image transfer to the transfer material, the apparatus stops with untransferred toner particles adhering to the intermediate recording medium. In this state, when the poorly conveyed transfer material is removed and the device is driven again, the toner adhering to the intermediate recording medium enters the nip between the intermediate recording medium and the transfer roller), and the toner is transferred to the surface of the transfer roller. is offset and [, Mari. If the subsequent image transfer operation is performed with toner adhered to the surface of the transfer roller in this way, the back side of the transfer material (
(Back side of the image recording surface) The toner on the K transfer roller will adhere and stain the back side of the transfer material.

In addition, if the toner adhering to the surface of the transfer row 2 becomes abundant and comes into contact with the surface of the intermediate recording medium, the toner may fuse to the surface of the intermediate recording medium. In this case, not only the surface of the intermediate recording medium becomes dirty but also , the electrostatic characteristics, surface resistance, etc. of the surface change, so that the quality of the image recorded by the image recording device is significantly degraded.

1. Purpose of the Invention The present invention has been made in view of the above points, and it is an object of the present invention to provide an improved image recording apparatus that solves all of the above-mentioned problems.

Summary of the Invention The present invention relates to an image recording apparatus that transfers an image formed on an intermediate recording medium to a transfer material by pressure using a transfer roller that is pressed against the intermediate recording medium, and a cleaning means for cleaning the transfer roller. [7] is provided so that unnecessary developer on the intermediate recording medium is once transferred to the transfer roller and then removed from the transfer roller.

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

FIG. 1 is a sectional view schematically showing essential parts of an embodiment of an image recording apparatus embodying the present invention.

In FIG. 1, a dielectric layer is provided on the outer peripheral surface of a cylindrical conductive substrate such as a metal drum, which is an intermediate recording medium, and is rotationally driven in the direction of the arrow by a driving means (not shown). An ion generator 2 serving as a recording head selectively emits ions to the drum 1 according to an image information signal inputted by an image information signal input means (not shown).
A dot-shaped electrostatic latent image corresponding to image information is formed on the outer peripheral surface of the drum 1, the details of which will be described later.

The developing device 3 is used to visualize the electrostatic latent image formed on the tram 1 by the ion generator 2 using toner as a developer, and includes a toner container 3a containing the toner and a toner container 3a that stores the toner on the surface of the drum 1. and a rotatable developing roller 3b. Therefore, the image information signal input means, the ion generator 2, and the three developing devices constitute an image forming means for forming an image on the drum 1, which is an intermediate recording medium.

On the other hand, transfer paper 5 which is a transfer material loaded in the cassette 4
are conveyed into the apparatus main body 91 sheets at a time by rotation of a paper feed roller 6 which is rotatable by a drive means (not shown), and by rotation of a register roller 7 which is rotatable by a drive means (not shown) at a predetermined timing. , the image gI formed on the transfer paper 5 and the drum 1! Positional synchronization with (toner image) is performed. Therefore, the paper feed roller 6, the register roller 7, and their driving means are elements constituting a transfer material transport mechanism that transports the transfer paper 5, which is a transfer material.

A transfer/fixing device is provided, which includes a transfer roller 9 with a high capacity and a biasing force stamp and means shown in FIG. The transfer roller 9 has its shaft 10 pressed by a pressure M coil spring 1 as a biasing force applying means.
1 against the tram l, and is brought into pressure contact with the drum IK at the transfer and fixing position 8 shown in FIG. As the transfer roller, for example, a low member having an elastic layer of resin such as polyacetal resin about 2 to 10 times thick on the surface of a core metal material such as a steel pipe can be used.

The transfer paper 5 is transferred to the transfer fixing position 8 by the transfer material conveyance mechanism described above.
The toner particles formed on the drum 1 are transferred onto the transfer paper 5 by the pressure between the drum 1 and the transfer roller 9. At the same time, the pressure fixes the image onto the transfer paper. Thereafter, the transfer material 5Fi is separated from the tram 1 by a transfer material separation means (not shown), passes through a guide G1, and is then discharged onto a tray 13 (by a paper discharge roller 12 driven by a drive means (not shown)).

On the other hand, the residual charge on the surface of the drum 1 after passing through the transfer position 8 is removed by the corona discharger 14, and the drum 1 is prepared for the next step formation.

Further, a cleaner 30 serving as a cleaning means is provided on the transfer roller side, and is configured to clean the surface of the transfer roller 9 with a cleaning blade 31. This cleaner will be detailed later.

FIG. 2 is a diagram showing details of the recording head 2 used in the embodiment shown in FIG. 1, and is a sectional view showing a portion of the recording head corresponding to one dot of the dot-shaped electrostatic charge pattern.

Incidentally, electrostatic recording in which multiple images are recorded by emitting ions and forming a dot-shaped electrostatic charge pattern on a dielectric drum is disclosed in, for example, JP-A-54-53537 and JP-A-54-7.
It is known from No. 8134 etc.

As shown in FIG. 2, the recording head includes a plurality of parallel drive electrodes 21 extending in the axial direction of the drum 1, and a plurality of parallel control electrodes 22 extending in a direction crossing the drive electrodes 21. These drive electrodes 21 and control electrodes 22 overlap in the vertical direction in FIG. 2 to form a matrix structure.

Each control electrode 22KFi preferably has a groove or hole 22& formed along its longitudinal direction, and each intersection of the groove or hole portion and the drive electrode 21 corresponds to one dot of the electrostatic charge pattern.

The recording head further includes a drive electrode 2 with respect to the control electrode 22.
The screen electrode 23 has a screen electrode 23 provided on the opposite side of the electrode 1, and a plurality of screen openings 23a are formed in a matrix at 7 corresponding to the intersections of the drive electrode 21 and the control electrode 22. . Dielectrics 20a and 20b are provided between the drive electrode 21 and the control electrode 22 and between the control electrode 22 and the screen electrode 23, respectively, to isolate these electrodes from each other.

A suitable AC voltage (
For example, a peak-to-peak voltage of about 1 to sKV) is applied, and as a result, a creeping discharge occurs along the interface between the control electrode 22 and the dielectric 20&, and ions are generated. At this time, an appropriate DC bias (for example, about 300 to 90
When a voltage of about 0 V) is applied, the creeping discharge occurs frequently,
The ions flow toward the drum 1. If this DC bias is negative, the ion flow is negative (minus), and if it is positive, it is positive (
Plus) ion flow. On the other hand, a constant bias is applied to the screen electrode 23, and by alternately changing the potential of each control electrode 22 to a value before and after the bias value to the screen electrode 23, the dielectric of the drum l is Layer l
The generation of ion flow onto a can be controlled by 0N10FF.

As mentioned above, the screen electrode 23 has a plurality of screen openings formed in a matrix, corresponding to the matrix structure composed of the drive electrodes 21 and the control electrodes 22. By controlling the potential as described above, any dot-shaped electrostatic charge pattern can be formed on the dielectric layer la of the drum 1.

Next, the cleaning means in the image recording apparatus of the present invention will be explained.

FIG. 3 is a perspective view schematically showing the vicinity of the beam means. The cleaner 30 (frame body not shown) has a leaning blade 31 as shown. As the cleaning blade 31, for example, a plate spring member such as a stainless steel plate for a spring, a phosphorescent copper plate, or a rubber member such as urethane rubber can be used. The cleaning blade 31 is fixed between two sheet metal members 32 and 33. 33 sheet metal members, swing member 34, bin 3
5, it is rotatably supported in the direction of arrow A with the bottle 35 as the center.

On the other hand, the swinging member 34 is rotatably supported in the direction of arrow B by pins 36 and 37 fixed to a side plate of the main unit (not shown). Further, the swinging member 34 is biased by tension springs 38 and 39 (one end of which is fixed to a side plate of the main unit (not shown)), so as to push and attach the cleaning blade 31 to the surface of the transfer roller 9. There is. Incidentally, it is preferable that the force for pressing L7 is about several tens to several hundred 9/am in the longitudinal direction of the cleaning blade 31.

The configuration as described above has the following advantages.

For example, in order to equalize the pressure between the drum and the transfer roller, the drum 1 and the transfer roller 9 may be arranged so that the axis of the drum 1 and the axis of the transfer roller 29 intersect with each other. At this time, the axis of the transfer row 29 may be tilted relative to the main unit, but the cleaning blade 31 is rotatable relative to the swinging member 34 in the direction of arrow A as described above. , and the swinging member 34 is rotatable in the direction of arrow B relative to the main unit 7, so that the cleaning blade 31 can always be pressed with a uniform pressing force over the longitudinal direction of the transfer row 29. . The same applies to the case where the transfer row 29 itself is eccentric L7. Therefore, the surface of the transfer roller can be cleaned well.

By the way, when an image recording device with good transfer efficiency is operating normally, most of the toner image formed on the drum 1 is transferred to the transfer material within the nip between the drum 1 and the transfer roller 9. Almost no toner remains on the drum surface after image transfer.

However, if the device stops operating due to a transfer material failure, etc., untransferred toner remains on the drum, so when the device is restarted, the surface of the drum 1 will be removed. The upper toner is offset to the transfer roller 9. At this time, the transfer efficiency of toner from the drum to the transfer roller is approximately equal to the transfer efficiency of toner from the drum to the transfer material, and therefore, almost all of the residual toner on the drum is offset to the transfer roller. Therefore, there is no need to apply cleaning means to the drum, and the cleaning means does not abrade the drum surface. Therefore, it is possible to prevent the durability of the drum from decreasing.

On the other hand, the toner offset onto the transfer roller 29 is scraped off the surface of the transfer roller 9 by the cleaning blade 31, so that the transfer roller 9 is constantly cleaned. In this way, all the toner that has been offset [7] on the transfer roller 9 is removed before entering the nip between the drum and the transfer roller 2, so the toner does not adhere to the drum again and the toner is fused to the drum surface. can be prevented.

In the above embodiment, the cleaning blade 31 was used as the cleaning means, but the same effect can be obtained by using other cleaning methods such as an abrasive roller or a web cleaner.

Therefore, the cleaning means H% of the present invention is not limited to the blade cleaning method, and other methods such as IJ-
It is also possible to apply a matching method.

Further, in the illustrated embodiment, a drum having a dielectric layer on the outer peripheral surface is used as the intermediate recording medium, an electrostatic latent image is formed by an ion generator, and the image is then visualized by a toner developer. However, the present invention can be applied to all devices in which an intermediate recording medium and a transfer roller are in pressure contact and transfer toner particles to a transfer material within a nip between the two. However, the image forming method is not limited to the above method.

Further, in the above-mentioned embodiment, a case was shown in which fixing was performed at the same time as pressure transfer, but the present invention is not limited to this. Of course, it is also possible to establish greatness by other means.

As described above, according to the present invention, it is possible to prevent toner from adhering to the intermediate recording medium, and it is also possible to prevent the durability of the intermediate recording medium from decreasing.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of an image recording apparatus to which the present invention is applied. FIG. 2 is a sectional view showing the ion generator used in the first embodiment. FIG. 3 is a perspective view schematically showing the vicinity of the cleaning means. 1...Intermediate recording medium 2...Ion generator 3...Developer 5...Transfer sheet 9...Transfer roller 11...Biasing force applying means 30...
...Cleaner 31...Cleaning blade

Claims (1)

[Claims] an intermediate recording medium, an image forming means that forms an image on the intermediate recording medium, a transfer roller that transfers the image formed on the intermediate recording medium to a transfer material by pressure, and a transfer roller that transfers the image formed on the intermediate recording medium to the intermediate recording medium. An image recording apparatus comprising: a biasing force applying means for applying a biasing force to a transfer roller to bring the transfer roller into pressure contact with the transfer roller; and a cleaning means for cleaning the transfer roller.