JP2738858B2 - Cleaning equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a cleaning device provided in a copying machine or the like.

(Prior Art) In FIG. 5, reference numeral 1 denotes a drum-shaped photosensitive member, and the photosensitive member 1 is rotated clockwise. A toner image is formed on the photoconductor 1 by a known image forming apparatus (not shown). Then, transfer paper 10 is supplied onto the photoreceptor 1 from a paper feeding device (not shown), and the toner image on the photoreceptor 1 is transferred onto the transfer paper 10 by the transfer charger 9.

The transfer paper onto which the toner image has been transferred is separated from the photoreceptor 1 by the action of a separation claw or the like, and the transfer paper 10
After the upper toner image is fixed, the toner image is discharged outside the apparatus.

Reference numeral 3 denotes a cleaning roller, and the cleaning roller 3 is in contact with the photoconductor 1. The cleaning roller 3 is provided in a cleaning tank 7. Further, a squeezing roller 4 that is in pressure contact with the cleaning roller is provided in the cleaning tank 7. The cleaning roller 3 has a liquid supply port 6 and a diffusion plate 5.
A cleaning liquid composed of a developer is supplied through the.

The cleaning device 13 is constituted by the cleaning roller 3, the tank 7, the liquid supply port 6, and the diffusion plate 5.

The cleaning roller 3 rotates counterclockwise to remove the toner remaining on the photoconductor 1 after the transfer operation is completed. Further, the cleaning liquid on the photoconductor 1 is removed by the blade 2.

In this copying machine, a sensor is arranged in the transfer paper discharge path, and after the transfer operation, the transfer paper 10 does not separate from the photoreceptor 1, so that when the sensor does not detect the passage of the transfer paper, a jam occurs. Is displayed or the copier is stopped.

(Problems to be Solved by the Invention) However, when a part of the transfer paper that has caused the jam has entered the cleaning tank 7, the user does not notice this and turns the switch off and on again to start the copying machine. When activated, the transfer paper may wind around the cleaning roller 3, and the transfer paper may damage the surface of the photoconductor 1. If the surface of the photoreceptor 1 is damaged, white streaks or black streaks will occur in the copied image.

In addition, when the transfer is wound around the cleaning roller 3, not only the cleaning function is not fulfilled, but also the liquid holding ability of the cleaning roller 3 is reduced, and dripping occurs, thereby causing stains on the copied image and the peripheral area of the cleaning device 13. There is a risk of soiling the device. Further, if the dripping continues for a long time, the developer may leak out of the copying machine.

(Means for Solving the Problems) The present invention has been made to solve the above-mentioned conventional problems, and a toner image formed on a photoreceptor having a potential equal to or higher than a certain value is transferred to transfer paper. A cleaning member provided in contact with the photoconductor to remove toner remaining on the photoconductor after the cleaning, the cleaning member is disposed in an electrically insulated state. An image forming apparatus is provided in which at least a portion in contact with a photoreceptor is formed of a conductive material, and a current detecting means is connected to a conductive portion of the cleaning member.

(Operation) According to the present invention, the cleaning member is disposed in an electrically insulated state, and at least a portion in contact with the photoconductor is formed of a conductive material. Since the value detecting means is connected, a current of a constant value flows from the photoconductor to the cleaning member, and this current is detected by the current value detecting means.

Further, when a jam occurs and the transfer paper is caught between the photosensitive member and the cleaning member, the current value detected by the detection unit decreases.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

The cleaning device of the present invention shown in FIGS.
Except that the cleaning member is made of a conductive material and that the current value detecting means is connected to the cleaning member, the structure is the same as that of the conventional example. In the following description, the same reference numerals as those in the conventional example will be used for other components, and the description thereof will be omitted.

In FIG. 1, reference numeral 21 denotes a cleaning roller as a cleaning member.
Is formed of a conductive rubber which is a conductive material. The cleaning roller 21 is connected to an ammeter 23 as current value detecting means.

Next, a jam sheet detection operation of the cleaning device of the embodiment will be described.

As shown in FIG. 1, the transfer charger 9 transfers the toner image on the photoreceptor 1 to the transfer paper 10. At this time, the photoreceptor 1 is also charged to a certain potential or higher, so that the current value measured by the ammeter 23 in a normal state is a value equal to or higher than a certain value R as shown by a symbol A in FIG. .

Now, the transfer paper 10 is conveyed to the position facing the cleaning roller 21 while being attracted to the photoreceptor 1 without being separated from the photoreceptor 1 irrespective of the action of the separation claw or the like, and the transfer paper is removed as shown in FIG. When the transfer paper 10 is wound around the cleaning roller 21 and interposed between the photosensitive member 1 and the cleaning roller 21 as shown in (2), the resistance value between the photosensitive member 1 and the cleaning roller 21 increases. , The ammeter 23 indicates a value equal to or less than a predetermined value, which is indicated by a symbol B in FIG. 3, and indicates the jam of the transfer paper.

In FIG. 3, a threshold value indicated by an alternate long and short dash line R is set,
If the measured current value is equal to or larger than the threshold value, the copying machine can be operated normally, and if the measured current value is equal to or smaller than the threshold value, a means for stopping the copying machine can be provided.

In the above embodiment, the entire cleaning roller 21 is formed of a conductive material. However, only the portion that comes into contact with the photoreceptor 1 may be formed of a conductive material like the cleaning roller 31 shown in FIG. . Further, as shown in FIG.
You may make it connect to the ammeter 23 via 33.

Further, the present invention is not limited to the case where the present invention is applied to the wet type copying machine described in the embodiment, but can be of course applied to a dry type copying machine. In this case, an ammeter is connected to a cleaning brush as a cleaning member.

Further, the present invention can be applied to facsimile machines and various printers.

(Effect of the Invention) As described above, according to the present invention, when the transfer paper is wrapped around the cleaning member, it is possible to measure the decrease in the current value and detect that the transfer paper is wrapped around the cleaning member. Therefore, with the transfer paper left in the cleaning device,
It is possible to prevent the device from being restarted. Therefore, it is possible to completely eliminate an accident such as damage to the photoconductor.

[Brief description of the drawings]

1 and 2 are views showing the cleaning apparatus of the present invention by operation, FIG. 3 is a graph showing a change in current value corresponding to the operation of the cleaning apparatus of FIGS. 1 and 2, and FIG. FIG. 5 is a diagram showing a second embodiment, and FIG. 5 is a diagram showing a conventional example. 1 photoreceptor, 9 transfer charger, 10 transfer paper, 13 cleaning device, 21, 31 cleaning roller, 23 ammeter, 33 squeeze roller

Claims (1)

(57) [Claims] An image forming apparatus comprising: a toner image formed on a photoconductor having a potential equal to or higher than a predetermined value; and a toner image formed on the photoconductor. The cleaning member is disposed in an electrically insulated state, and at least a portion in contact with the photoreceptor is formed of a conductive material. A current value detecting means connected to the conductive portion of the cleaning device.