JPH02255357A - Image forming apparatus - Google Patents

Abstract

PURPOSE:To correctly set a leading edge of a paper in a simple manner with high speeds by providing a transferring means which has a recording medium supporting member for fixedly supporting a recording medium and transfers a color agent on a transfer material while moving said recording medium in the printing direction, so that said recording medium supporting member is automatically returned to a front end of said recording medium after the transfer. CONSTITUTION:A paper bed 31 supported by a supporting arm 32 transfers a paper P in a printing direction in accordance with the rotation of a platen roller 22, and an ink on a transfer ribbon 23 is transferred to the paper P by printing of a thermal head 21, thus forming an image. After the first printing is finished, with the thermal head being detached from the platen roller 22, the paper bed 31 is dropped by its own weight to the position of a front end of the paper 9 by utilizing the weight of a mass body 34. Accordingly, the paper bed 31 is automatically returned to the front end of the paper P. Thus, the front end of the recording medium for every color can be set in a simple manner with high speeds regardless of the size of the medium.

Description

Detailed Description of the Invention [Objective of the Invention] (Industrial Application Field) The present invention relates to an image forming apparatus applied to multicolor image formation, such as a color copying machine or a color printer, and particularly relates to The present invention relates to an image forming apparatus in which a means for locating and transporting a recording medium is improved.

(Prior art) In recent years, recording media (hereinafter referred to as paper) are coated with transfer materials (hereinafter referred to as paper).
An image forming apparatus that forms a desired color image by transferring a plurality of colorants (hereinafter referred to as ink) from a recording head (hereinafter referred to as a thermal head) from a transfer ribbon has been developed and put into practical use. has been done.

In such an image forming apparatus, as a means for positioning the paper during color image formation, 1, for example, a platen roller is used to move the paper held between the thermal head in the printing direction as the platen roller rotates. There is a high-speed return method in which the paper is returned by transferring the ink from the transfer ribbon and rotating the platen roller in the reverse direction at high speed after the first printing is completed.

Another method is to use a large-diameter drum-shaped platen, and use a fixing device called a gripper to support and fix the leading edge of the paper and wind it. Some printers are configured so that the platen rotates exactly once, thereby locating the next color.

(Problem to be Solved by the Invention) However, with the above-mentioned paper cueing method using high-speed reverse rotation of the platen roller, even if it is returned at high speed, it takes several seconds, reducing the overall printing speed. It is inevitable that it will happen.

In addition, when using a paper cueing method that uses a large-diameter drum-shaped platen, the platen must be matched to the maximum paper size used, and if the paper size is smaller, the extra paper head due to high-speed rotation of the platen must be adjusted. It takes time to put it out,
Again, this reduces the overall printing speed.

As a solution to this case, it may be possible to equip a plurality of platens and thermal heads according to the paper size, but this cannot be said to be practical in terms of cost.

The present invention was made under the above circumstances, and its purpose is to
It is an object of the present invention to provide an image forming apparatus that can perform accurate sheet positioning simply and at high speed.

[Structure of the Invention] (Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention provides a platen roller, a recording head section positioned facing the platen roller so as to be able to approach and separate from it, and this recording head. A recording medium supporting member is provided between the unit and the platen roller for supporting and fixing the recording medium fed, and the colorant on the transfer material is transferred while the recording medium is transported in the printing direction as the platen roller rotates. and a transfer means for transferring, and the transfer means is configured to automatically return the recording medium support member to the leading position of the recording medium after the transfer. In this case, the transfer means As a means for automatically returning to the leading position of the recording medium after transfer, it is preferable to use the fall of the recording medium support member under its own weight or a biasing force such as a spring.

(Function) That is, in the present invention, the recording medium fed between the recording head section and the platen roller is supported and fixed on the recording medium support member of the transport means, and the recording medium support member is transferred after transfer. In order to automatically return to the beginning position of the recording medium.

Regardless of the size of the recording medium, you can easily and quickly locate the beginning of the recording medium for each color.
Printing speed can be improved.

In addition, since the recording medium is supported and fixed to the recording medium support member of the transport means and transported, there is no lateral shift of the recording medium.
Accurate cueing of the recording medium can be performed.

(Example) Hereinafter, the present invention will be described in detail with reference to an illustrated example.

FIG. 2 schematically shows the overall internal configuration of an image forming apparatus according to the present invention, and 1 in the figure is the main body of the apparatus. A document table 2 is arranged on the upper surface of the apparatus main body 1, and a document holding cover 3 is provided on the document table 2.

Further, in the apparatus main body 1, a document scanning section (scanner section) 4 is disposed at the top to scan a document set on a document table 2 from below, and an image forming section (printer section) is disposed at the bottom. Section) 5 is arranged.

The document scanning section 4 includes a first mirror 8 having an exposure lamp 7 whose back part is surrounded by a reflector 6 and a first mirror 8.
a moving optical block 9, a second moving optical block 12 having a second mirror 10 and a third mirror 11, a fixed optical block 16 having a fourth mirror 14 and a fifth mirror 15, and a photoelectric conversion By moving the first movable optical block 9 along the document tray 2, the image plane of the document tray is optically scanned, and the optical information thereof is transmitted. The direction is reflected to a second moving optical block 12 that moves at half the speed of the first moving optical block 9, and the optical information reflected by this second moving optical block 12 is transmitted to a lens 13 and a fixed optical block. The signal is received by a photoelectric converter 17 via a filter 16, and is input to the image forming section 5.

On the other hand, the image forming section 5 includes a platen roller 22 located approximately in the center of the apparatus main body 1, and a platen roller 22 located approximately in the center of the apparatus main body 1.
2, a transfer ribbon 23 interposed between the thermal head 21 and the platen roller 22, and both ends of the transfer ribbon 23 passing through guide rollers 24 and 25. A transport means 3o that supports and fixes the paper P from the paper feed cassette section 28 that is fed between the cores 26 and 27 that are wound around the thermal head 21 and the platen roller 22, and transports it in the printing direction.
It is composed of.

That is, the transfer means 3o, as shown in FIG.
A plate-shaped paper table 31 serving as a recording medium support member having a smooth curved surface is interposed between the thermal head 21 and the platen roller 22, and a rotatable support that supports the upper end of this paper table 31. An arm 32 and a gripper that is provided at the upper end of the paper table 31 and that grips the leading end of the paper P fed between the thermal head 21 and the platen roller 22 and supports and fixes it on the paper table 31. 33, and a mass body 34 provided at the lower end of the paper tray 31.

The paper table 31 supported by the support arm 32 moves the paper P in the printing direction as the platen roller 22 rotates, thereby transferring the ink on the transfer ribbon 23 to the paper P by printing from the thermal head 21. Transfer it to
When the first printing is completed and the thermal head 21 is separated from the platen roller 22, the weight of the mass body 34 is used to move the paper as shown in FIG. The stand 31 is dropped and moved by its own weight to the leading position of the paper P, and is automatically returned to the leading position of the paper P.

In the above embodiment, the paper table 31 is connected to the mass body 3.
Although the paper P is automatically returned to the leading position by its own weight using the weight of the paper P, it is also possible to use a biasing force such as a spring to pull the paper P back.

In addition, it goes without saying that the present invention can be modified in various ways without departing from the gist of the invention.

[Effects of the Invention] As is clear from the above description, according to one aspect of the present invention, a platen roller, a recording head portion positioned facing the platen roller so as to be able to approach and separate from the platen roller, and a connection between the recording head portion and the platen roller. a transfer means that has a recording medium support member that supports and fixes the recording medium fed therebetween, and that transfers the colorant on the transfer material while conveying the recording medium in the printing direction as the platen roller rotates; The transfer means is configured to automatically return the recording medium supporting member to the leading position of the recording medium after the transfer.

It is possible to easily and quickly locate the beginning of a recording medium for each color, regardless of the size of the recording medium, and thereby the printing speed can be improved.

In addition, since the recording medium is supported and fixed to the recording medium support member of the transport means and transported, the recording medium does not shift laterally, and the recording medium can be accurately positioned, which is an excellent effect. It is something.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram showing one embodiment of a paper cue means in an image forming section of an image forming apparatus according to the present invention;
This figure is a schematic cross-sectional view showing the overall configuration of the image forming apparatus, and FIG. 3 is a schematic explanatory view showing the operating state of the paper cue means in the image forming section. 5. P. Main body of the device, image forming section (printer section), - recording head section (thermal head), - platen roller.・Transfer material (transfer ribbon), ・Transfer means, ・Recording medium support member (paper table).・Support arm, ・Gripper, 34...mass body, paper.

Claims (1)

[Claims] A recording medium support member that supports and fixes a recording medium fed between the recording head section and the platen roller; a transfer means for transferring the colorant on the transfer material while transferring the recording medium in the printing direction as the platen roller rotates, the transfer means comprising:
An image forming apparatus characterized in that the recording medium support member is configured to automatically return to the leading position of the recording medium after transfer.