JPS58167347A - Printer - Google Patents

Abstract

PURPOSE:To prevent a sheet of paper from becoming up side down or unregistered when the opposite surfaces of the sheets are printed, by turning the sheet without changing the advancing direction of the sheet when the sheet that has left a transferring and fixing section is returned to said section. CONSTITUTION:The sheet from a hopper is sent to the transferring and fixing section 1 and the one side thereof is first printed. Then the sheet 1 is sent using a paper delivering mechanism 6 by a command from a control section 7 to a turning section 5 where the delivery of the sheet is detected, and the sheet is turned 180 deg., and the surfaces thereof are also reversed. Then the sheet is sent again to the transferring and fixing section 1, and after the other side of the sheet is printed and the sheet is sent to a stacker 5 by a command from a control section 7. In this case an optical sensor is used for detecting the arrival of a sheet, and when a sheet carried on a tray 10 cuts off the light between a luminescent element 8 and a light receiving element 6, the fact is detected by the optical sensor. Then the tray 10 is rotated 180 deg. by a rotating shaft 12.

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention The present invention relates to a printing device. In particular, the present invention relates to a printing apparatus capable of performing double-sided printing, and relates to control of paper feeding in the printing apparatus.

Prior Art Conventional printing devices are typically only capable of single-sided printing. When double-sided printing is performed in such a printing device, one-sided printing is first performed, and then the printed paper is returned manually and inputted again to the printing t& position. The above method has the disadvantage that manual operations are required during the process, which may result in a single operation, and that manual operations are always required. Among printing devices capable of double-sided printing, there is a device that performs paper feeding control as shown in FIG. The sheet outputted from the transfer/fixing section 1 is fed to the advancing direction reversing section 2, the advancing direction is reversed, and the paper is inputted into the transferring/fixing section 1 again. As can be seen from FIG. 1, the front and back sides of the paper are reversed, but the direction of travel of the paper is reversed. As a result, the top, bottom, and left/right directions of the paper differ between the six sides and the back side. In order to improve the above-mentioned problem, it is sufficient to reverse the print data. For example, paper v/! When printing one side, output the print data starting from the top right of the page, and print out the print data from the top right of the page. When printing a page, the print data can be output from the bottom left of the page. However, in the above method, the surface of the paper, I! When printing kIf[i, a hardware to control data output is required, and data output control is also complicated.

OBJECTS OF THE INVENTION An object of the present invention is to improve the above-mentioned drawbacks and to provide a double-sided printing apparatus that does not require human labor and is controllable and insecure, capable of reversing the upper dpi data output.

SUMMARY OF THE INVENTION In the present invention, when the paper output from the transfer/fixing unit is returned to the input of the transfer/fixing unit, only the front side and back side of the paper are reversed without reversing the traveling direction of the paper. When performing double-sided printing, the surface of the paper and the I! This is to prevent the top, bottom, left, and right of the page from being reversed.

Embodiment of the Invention An embodiment of the invention is shown in FIG. This will be explained below according to the diagram. The paper in hopper 3 is sent to transfer/fixing & 151,
First, one side is printed. The next sheet output from the upper H transfer/fixing unit $1 is sent to the paper feed mechanism 64I according to a command from the control unit 7.
: Sent to the reversing section 5. The reversing unit 5 detects that the paper has been fed and rotates the plate 180 degrees in a direction perpendicular to the direction in which the paper travels. That is, the front and back sides of the paper are reversed. An optical sensor is used to detect that the paper has been fed. That is, as shown in FIG. 3, the paper is placed on the tray 10 and blocks the light between the light emitting element 8 and the light receiving element 9, whereby detection is performed. Further, as other detection methods, detection of the leading edge of the paper or detection of the weight may be used. When it detects that the above paper has been sent, the above paper is transferred to the paper fixing device 1.
1 (this is a U-shaped piece of wire that rotates in response to an air permeation signal with the upper part in the figure as a fulcrum).

Next, the saucer 10 is moved around the rotating shaft 12 by a motor.
The rotation plate rotates 80 degrees. When the rotation plate is rotated 180 degrees, the paper fixing device 11 is removed, and the paper holder 11 is removed.
It is sent to the above-mentioned transfer foot side I by II6. At this time, it is clear that the front and back sides of the paper are reversed compared to when the paper is printed for the first time in jIk and the next time. The paper that has been double-sided printed in the transfer/fixing section 1 is transferred to the control section 7.
It is sent to the stacker 5 by the 0 command. Then again hopper 6
A sheet of paper is taken out and sent to the transfer/fixing section 1, whereupon the same operation is performed.

In this way, when the paper is input to the transfer/fixing section 1, multiple inputs will always be made to a certain portion of the paper, regardless of whether the paper is on the front or back. For this reason, the data to be printed on the paper should always be output from a certain position on the page, for example, from the upper left, regardless of the front or back sides of the paper. It is also obvious that the paper feeding mechanism 6 may be twisted between the exit and entrance of the transfer/fixing section 1 so as to rotate the paper 180 degrees without using the upper d-pi reversing section 5.

Effects of the Invention According to the present invention, double-sided printing can be performed without requiring manual labor. Therefore, it is possible to improve office efficiency. Furthermore, there is no need to change the method of outputting stamp data between the front and back sides of the paper, and hardware can be reduced.

Also, by printing on both sides of the paper and using only one side, there is no need to change the paper when it is to be used again. For example, when printing only on the front side at first and then switching to the back side halfway through, according to the present invention, the front and back sides of the paper are automatically reversed, so there is no need to change the paper.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of a conventional paper feeding method during double-sided printing. The second factor is a diagram showing an embodiment of the present invention. FIG. 3 is a detailed view of the inversion part in FIG. 2. 1: Transfer/fixing section, 2: Moving direction rotating section, 3: Hopper,
4: stacker, 5: reversing section, 6: paper feeding) fa structure, 7: control section, 8: light emitting element, 9: light receiving element, 10: saucer, 11
: Paper fixer, 12: Rotating shaft. 1st m 2nd

Claims (1)

[Claims] One side of the paper is printed on the transfer/fixing unit, and then the back side of the paper is printed! ! In a reverse KL, in a printing device capable of printing both sides of the paper by inputting it to the transfer/fixing section, the paper output from the transfer section is outputted before the transfer/fixing section. The present invention is characterized by having a paper feeding mechanism that inputs the paper first to the transfer/fixing section on the other hand, and rotating the paper half a rotation with respect to a plane perpendicular to the direction of paper feeding in the middle of the paper feeding mechanism. printing device.