JPH0350582A - Printer device - Google Patents

Abstract

PURPOSE:To obtain sufficient printing quality even immediately after starting printing by rotating a transfer plate through a link mechanism by driving a DC motor. CONSTITUTION:The transfer plate 2 is set to be separated from a photosensitive drum 1 by the link 3 driven by the DC motor 4 in a state other than a printing action state so that a recording paper 6 may not come into contact with the photosensitive drum 1. When a toner image approaches a transfer position, a BD tractor 8 is operated to control the recording paper 6 to be at a speed equal to that of the photosensitive drum 1. At the same time, the transfer plate 2 is actuated so as to make the photosensitive drum 1 and the recording paper 6 contact with each other. By impressing forward voltage, the DC motor 4 starts rotation in uniform acceleration, and by impressing reverse voltage, the motor 4 begins the decelerating rotation in the uniform acceleration and stops, then the transfer plate 2 performs the rotation in the larger acceleration through the link arm 3. While the action of the link mechanism 3 is accelerated, shock at the time of completing the action is reduced, and the printing quality immediately after starting printing is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a printer device, and particularly to a printer device using an electrophotographic process used for output of an information processing device or used in a copying machine, a printing machine, etc.

[Conventional technology]

In general, printer devices using an electrophotographic process require a transfer plate to bring the photosensitive drum and recording paper as close as possible to ensure print quality during print transfer. And you need to turn it around. Conventionally, as shown in FIGS. 8 and 9, the rotary solenoid 5
1 rotation was transmitted to the transfer plate 53 via the link mechanism 52.

[Problem to be solved by the invention]

In conventional printer devices, a rotary solenoid is used to operate the transfer plate, but since the rotary solenoid has a small rotation angle, the link mechanism has little freedom. In addition, the link tends to rattle, the rotation speed is slow, and the brake cannot be applied, so the shock after the operation is completed is large, causing the transfer plate to bounce.
The disadvantage is that the print quality is not good immediately after printing starts.

SUMMARY OF THE INVENTION An object of the present invention is to provide a printer device in which the degree of freedom of the link mechanism is adjusted to speed up the movement, reduce the shock at the end of the movement, and improve the print quality immediately after printing starts.

[Means to solve the problem]

The printer device of the present invention is configured such that a DC motor drives a link mechanism that operates a transfer plate in a printer device that uses an electrophotographic process.

〔Example〕

Hereinafter, the present invention will be explained in detail using the drawings.

FIG. 1 is a diagram showing the structure of a printer device according to the present invention. The paper running surface is composed of a transfer plate 2, a paper guide 5, and a shaft 7, on which a recording paper 6 is run by a BD tractor 8. During printing, the recording paper 6 comes into contact with the photosensitive drum 1, and the charged toner 10 is transferred onto the recording paper 6 by the electric field generated by the transfer charger 9.

At this time, the recording paper 6 and the photosensitive drum 1 are controlled to flow at the same speed. However, if a speed difference occurs between the recording paper 6 and the photosensitive drum 1 at the start or end of printing and they rub against each other, the image may become smudged by the residual toner 10 on the surface of the photosensitive drum 1, or the transferred image may be damaged by friction. This may cause blurring.

Figure 2 shows the state other than the printing operation, and shows the transfer plate 2.
is set away from the photosensitive drum 1 by a link 3 driven by a DC motor 4 so that the recording paper 6 does not come into contact with the photosensitive drum 1.

FIG. 3 shows the operation of the present invention in a time chart.

At the start of a printing operation, when the rotational speed of the photosensitive drum is first increased and controlled to a specified speed, writing of an electrostatic latent image by laser light is started and a toner image is formed on the photosensitive drum. When the toner image approaches the transfer position, the BD controller 8 is operated to control the recording paper 6 at the same speed as the photosensitive drum 1.
At the same time, the transfer plate 2 is operated to bring the photosensitive drum 1 and the recording paper 6 into contact, and at this point, a voltage is applied to the transfer charger 9 to transfer the toner image onto the recording paper 6.

The printing operation is completed by performing the above-mentioned operation order in reverse.

Since normal toner image transfer is not performed during the time l1 from when the recording paper 6 starts running to when the transfer plate 2 finishes its operation, the distance traveled by the recording paper 6 during this time 110 is designated as a margin as an unprintable area. It remains. Therefore, in order to shorten the time 11, the transfer plate 2 must be operated for a short time. FIGS. 4 and 5 show the movement of the link and transfer plate of the present invention, and FIGS. 6 and 7 show experimental results.

FIG. 6 shows the rotation of the DC motor, and is equal to the amount of movement of points A1 and A2 in FIGS. 4 and 5. FIG. 7 shows the amount of movement of the transfer plate, and represents the amount of movement of two points B1 and B in FIGS. 4 and 5.

The DC motor starts rotating at a constant acceleration when a forward voltage is applied, and changes to decelerated rotation at a uniform acceleration and stops when a reverse voltage is applied. At this time, the transfer plate performs rotational movement with greater acceleration via the link arm. Comparing Figures 6 and 7, it can be seen that the transfer plate travel time is shorter than the DC motor rotation time. This number 4 is due to the structure of the link mechanism, and the transfer plate almost completes its operation in the time from B1 to B32.

By doing this, sufficient print quality can be obtained even immediately after the start of printing, when the print quality was not good with conventional methods.

〔Effect of the invention〕

As explained above, the present invention rotates the transfer plate via the link mechanism to drive the DC motor.
The transfer plate can be moved in a short time of 20 msec or less, and the shock and noise during operation can be reduced by applying a reverse voltage to the brake. Further, by setting the operating angle of the DC motor shaft to 180 degrees using the link mechanism, it is possible to reduce the wobbling of the transfer plate caused by the wobbling of the link mechanism.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing one embodiment of the present invention, and FIG.
Figure 3 is a time chart during operation of the present invention, Figure 4 is a diagram showing the structure of the link and transfer plate of the present invention in a stopped state, Figure 5 is the start of printing in Figure 4. 6 is a graph showing the experimental results of the operating characteristics of the link mechanism according to the present invention; FIG. 7 is a bluff showing the experimental results of the operating characteristics of the transfer plate shown in FIG. 6;
9 and 9 are configuration diagrams showing an example of a conventional printer device. 1...Photosensitive drum, 2...Transfer plate, 3...Link arm, 4...DC
Motor, 5... Paper guide, 6... Recording paper, 7... Shaft, 8... BD}
transfer charger, 9...transfer charger, 10...
··toner

Claims (1)

[Claims] A printer device using an electrophotographic process, characterized in that a DC motor drives a link mechanism that operates a transfer plate.