JPS6237786B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cleaning device for an electronic printing device that cleans toner remaining on a transfer medium such as a photosensitive drum or an electrostatic drum and removes dust attached to the drum surface.

In a recording apparatus that uses a drum-shaped or endless medium as a transfer medium on which a latent image is formed, a predetermined process of forming a latent image, toner development, and transfer is repeated on the medium. For this reason, it is necessary to remove the excess toner remaining on the transfer medium after the transfer to the recording paper, and contact removal type and non-contact removal type have conventionally been proposed as means for this purpose. Contact removal methods include a method of bringing a rotating fur brush into contact with the transfer medium to remove the toner (fur brush method), a method using a web-like paper,
There are a method in which the toner is removed by pressing a cloth or the like against the transfer medium and the web is sequentially wound up, and a method in which the toner is removed by pressing a flexible roller or belt (for example, made of sponge) against the transfer medium.

This contact removal type cleaning device does not require a large structure compared to a non-contact type, and has the advantage of being able to remove toner efficiently, but on the other hand, it wears and damages the surface of the transfer medium and is a consumable item. There are drawbacks.

Particularly in cleaning devices that use paper webs, the lifespan of the webs is short and the webs must be replaced frequently, which is uneconomical. By the way, when considering the operating state of a recording device, there are two states: a state in which a latent image is not formed even when the photosensitive drum is rotating (called a standby state), and a state in which the photosensitive drum is stopped. The time is quite large. In such a state, it is not necessary to clean the drum surface under the same conditions as when printing. However, in a conventional cleaning device using a paper web, even in such a state, the paper web is wound up at the same high speed as when printing. For this reason, the paper web is discarded before its weave is not sufficiently filled with toner, and therefore the toner recovery efficiency of the paper web is poor, further worsening economic efficiency.

It is an object of the present invention to provide a cleaning device capable of eliminating such conventional drawbacks, improving the toner recovery rate of a paper web, and improving economic efficiency. By attenuating the feeding speed of the web-like paper when the transfer medium is being driven and no latent image is formed on the medium, and by stopping the feeding of the paper when the transfer medium is stopped. achieved.

The present invention will be explained below with reference to the drawings.

FIG. 1 is a schematic diagram of a conventional cleaning device, and FIG. 2 is an explanatory diagram illustrating the rotational speed of a drum serving as a transfer medium and a collection roller for feeding out a paper web.

In the figure, reference numeral 1 denotes a photosensitive drum as a transfer medium on which a latent image is formed by a means not shown, which is then visualized with toner and transferred to recording paper, and 2 refers to residual toner remaining on the photosensitive drum after the transfer. 3 is a feed-out roller that feeds out the paper web; 4 is a collection roller that presses the paper web onto the photosensitive drum and feeds the web fed out by the feed-out roller to a take-up roller; A winding roller is driven to wind up the web and apply appropriate tension to the web, 61 to 65 are gear groups, 7 is a motor, 8 is a switch, and 9 is a power source.

In the recording device shown in FIG. 1, power is supplied to the device,
Furthermore, when the switch 8 is turned on, the collection roller always rotates at a constant speed, regardless of whether it is in the printing state (PRT), standby state (WAT), or stopped state (STP), as shown in Figure 2, thereby rotating the paper web at a constant speed. I am making the transition.

By the way, in the standby state WAT, only a small amount of toner from the developing section adheres to the photosensitive drum, so there is no need to feed the paper web under exactly the same conditions as PRT during printing, and the speed can be lowered to save paper web. It is preferable to do so. or,
When the photosensitive drum is in a stopped state STP, there is no need to remove toner, and therefore it is preferable that the paper web is also stopped.

FIG. 3 shows an embodiment of the present invention in which the rotational speed of the collecting roller in the standby state is controlled to be lower than the speed in the printing state, and FIG. 4 illustrates changes in the feeding speed of the collecting roller.

In the figure, R ₁ and R ₂ are resistors, CN is the motor control circuit, and 7
is, for example, a speed control motor (trade name) manufactured by Oriental Motor Co., Ltd. In addition, in the figure,
The same parts as in FIG. 1 are given the same numbers.
Although 7 has been described as a speed control motor, any motor may be used as long as the speed can be easily controlled by applied voltage or other methods.

The switch 8 is appropriately switched to the contact a or b side by a state monitoring means (not shown). For example, in the printing state, the switch 8 is switched to the contact a side to make the speed of the paper web by the collection roller 4 match the circumferential speed of the drum, and in the standby state, the switch 8 is switched to the contact b side to rotate the collection roller. The speed is reduced to 1/5 to 1/10 of the printing state.

In addition, in FIG. 3, a suitable switch may be provided to stop the rotation of the collecting roller when in the stopped state.

FIG. 5 shows another example of the present invention, in which the drum and the motor are rotated in complete synchronization, and FIG. 6 is an explanatory diagram of the rotational speed of the collecting roller. 10
11 is a drum rotation motor, 11 is a power source for supplying voltage to the cleaner motor 7 and the drum motor 10, and 12 is a switch.

Since the cleaner motor and the drum rotation motor 10 are each connected in parallel to the power supply, each motor rotates in complete synchronization with each other.

That is, when the drum comes to a halt, the collecting roller also stops.

Although the example shown in Fig. 5 does not control the speed of the collecting roller in the standby state, this can be easily done by providing the switch 8 and resistors R ₁ and R ₂ shown in Fig. 4 on the cleaner motor side power supply line. Ru.

As described above, according to the present invention, since the feeding speed of the paper web is controlled according to each state of printing, standby, and stop, the toner collection efficiency of the web can be increased.
Moreover, the lifespan can be extended, and the effect is great.

[Brief explanation of the drawing]

Figure 1 shows a conventional cleaner device, Figure 2 explains the rotation speed of the collection roller, Figure 3 shows an embodiment of the present invention, and Figure 4 explains the rotation speed of the collection roller in Figure 3. 5 is another embodiment of the present invention, and FIG. 6 is an explanatory diagram of the rotational speed of the collection roller in FIG. 5. 1... Drum, 2... Paper web, 4... Collection roller, 7... Cleaner motor, 8, 12...
...Switch, 10...Drum motor.

Claims (1)

[Claims] 1. After a powder image formed on a transfer medium is transferred to a recording medium, the powder remaining on the transfer medium is removed by pressing a web-like paper against the transfer medium, and In a cleaning device for a recording device, the web-like paper is constantly pressed against the transfer medium, and the transfer medium is being driven so that a latent image is not formed on the medium. Not in standby state,
A cleaning device using web-like paper, characterized in that the speed at which the web-like paper is fed is lower than the speed at which the paper is fed when forming a latent image on a transfer medium. 2. The cleaning device according to claim 1, wherein feeding of the web-like paper is stopped when the transfer medium is stopped.