JPH05178470A - Printer - Google Patents

Abstract

PURPOSE:To prevent spending of a wasteful time during printing. CONSTITUTION:Sensors 20 and 21 which detect marks recorded on sheets charged in a feed sheet case 7 are provided. Thus, since a kind of the sheet can be decided before the feed of sheets, when a sheet is not a target sheet or the like, it can be discriminated before the feed of the sheet. Compared with a conventional type, rapid discrimination can be executed and wasteful sheet feed operation can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet discriminating method for an image printer which can accommodate various sheets.

[0002]

2. Description of the Related Art An image printer for printing a color image interposes an ink ribbon having three or four colors of ink applied in the lengthwise direction between a thermal line head having heating elements arranged and a sheet of paper. By supplying the color image signal decomposed into the
It is possible to print a color image of four colors or four colors. Papers used for printing include A4 and A5 size papers having different sizes, and OHP papers and ultra-thin papers having different sensitivities. The configuration of the image color printer is shown in FIG. In the figure, a sheet 1 is stored in a box-shaped sheet feeding case 7 whose upper side is opened, and is biased upward by a sheet feeding spring 3 via a sheet feeding plate 2. The paper feed roller 4 is arranged above the front end of the paper feed case 7. The paper feed roller 4 is rotatably supported at one end of a lever 5 which swings around a support shaft 6, and a drive component (not shown) such as a solenoid is connected to the other end of the lever 5. Has been done. At the time of printing, the paper feed roller 4 presses the paper 1 and the motor 1 (not shown) drives the paper 1 one by one. The fed-out paper is a pair of first transport rollers 11,
It is sandwiched between 12. When the sheet detection sensor 15 provided adjacent to the first transport rollers 11 and 12 detects that the sheet 1 is nipped, the pressure of the sheet feed roller 4 is immediately released. Then, the paper 1 is fed to the first transport rollers 11 and 1.
By the second conveyance, the second conveyance rollers 13 and 14 pass between the thermal line head, which is the printing section, and the platen, and the sheet feeding is completed. After the completion of feeding, the thermal line head 8 is pressed against the paper 1 via the ink ribbon 10 and the thermal line head 8 is energized to print. The thermal line head 8 is energized by being selected from various image data previously stored in the image memory in accordance with the size, sensitivity, etc. of the paper. The type such as the size and the sensitivity of the sheet 1 is determined by the state of the signal when the type determination black mark printed on the sheet 1 passes the sheet detection sensor 15 during conveyance.

[0003]

As described above, the detection of the type of paper is performed when the paper sent out from the paper feed case is
This is done when passing through the printing section. Therefore, when a paper different from the image data is fed, for example, the image data for A4 size paper is loaded in the image memory.
When the fed paper is an A5 size paper, printing cannot be performed even though the paper feeding operation is completed. In this case, the paper discharging operation is performed after the paper feeding is completed.
This causes a waste of time between pressing the print switch and obtaining a desired print image. Furthermore, when a non-designated paper having a different hardness or size is loaded, paper jam may occur at the time of paper feeding.

[0004]

According to the present invention, in order to solve the above problems, presence or absence of a mark is provided above a paper feed case at a position facing a mark printed on a paper stored in the paper feed case. A reflection type sensor for detecting the

[0005]

With the above structure, since the type of the sheet is determined before the sheet feeding operation, the loaded sheet and the image data in the image memory are compared, and it is immediately determined whether or not the sheet is the designated sheet. Be done.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. This embodiment is applied to an automatic paper feeding device of an image color printer using special paper as in the conventional example of FIG. 6, and in FIG. 1, the paper feeding case 7 is also a box-shaped box that is opened upward. , Paper 1 is stored, and paper 1 is
The lower sheet feeding spring 3 urges the sheet upward. Reflective optical sensors 20 and 21 are arranged above the paper feed case 7 so as to face the paper 1. Optical sensor 20,
Reference numeral 21 has a light emitting element and a light receiving element, and when a light beam emitted from the light emitting element is reflected on the sheet 1 and enters the light receiving element, the output signal changes from high to low.
The paper 1 is stored in the paper feed case 7 with the surface for printing on the lower side, and on the surface opposite to the printing screen of the paper 1, the so-called back surface, for example, A4 size dedicated paper 1a ( Second
In the drawing), black marks 16a and 16b are printed at two places, and the mark 17a is printed on the A5 size exclusive paper 1b (FIG. 3). Mark 1 on A5 paper 1b
7a is located at the same position as the mark 16a of the A4 size exclusive paper 1a when it is loaded in the paper feed case 7 with the right ends thereof in the figure, and further, is located directly below the optical sensor 20. ing. The mark 16b is located directly below the optical sensor 21. Due to such a configuration, when the A4 size exclusive paper 1a is stored, the optical sensors 20, 21
In both cases, high light is output without reflection, and when the A5 size special paper 1b is stored, the optical sensor 20 outputs high and the optical sensor 21 outputs low. In addition, the paper other than the designated paper does not have a detection mark, so that the photosensors 20 and 21 both output a row. FIG. 4 shows an example of the configuration of a circuit for detecting the type of paper and controlling accordingly. Further, FIG. 5 shows a flowchart. The signal from the optical sensor 20 is given to the system control unit 30 and, as a result of the judgment, if it is low, an error display 31 displays an error. (Fig. 5 Step 4
1, 50, 51) Next, similarly, the signal of the optical sensor 21 provided to the system control unit 31 is determined, and if the signal is high, the A4 image data in the image memory 32 is provided to the head drive circuit 33. (Steps 42, 43 and 44 in FIG. 5) However, if the A4 image data is not stored in the image memory 32, the error display 31 displays an error. (Step 52 in FIG. 5) On the other hand, when the signal of the optical sensor 21 is low, the A5 image data in the image memory 32 is given to the head drive circuit 33. (Steps 48 and 49 in FIG. 5) However, if the A5 image data is not stored in the image memory 32, the error display 31 displays an error. (FIG. 5, step 51) As described above, in this embodiment, the output of the optical sensors 20 and 21 mounted on the paper feed case determines the paper before the paper feed operation to determine whether printing is possible. It is possible. Further, in this embodiment, the size of the paper is detected by the two optical sensors, but it is possible to make various kinds of discrimination by increasing the number of marks on the paper and the optical sensors.

[0007]

As described above, according to the present invention, the type of the paper is detected by the optical sensor provided on the paper feed case before the paper feed operation is performed. It is possible to eliminate waste of time in the case of non-conformance of (1) and to prevent paper jam at the time of paper feeding.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing a back side of an A4 sheet.

FIG. 3 is a diagram showing a back side of an A5 sheet.

FIG. 4 is a control block diagram of an embodiment of the present invention.

FIG. 5 is a flowchart of an embodiment of the present invention.

FIG. 6 is a diagram showing a configuration of a color printer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Paper 2 Paper feed plate 4 Conveying mechanism (paper feeding roller) 7 Paper feeding case 8 Printing mechanism (thermal line head) 9 Platen 10 Ink ribbon 16a, 16b, 17a Non-sensor part (mark) 20, 21 Sensor means (light sensor) )

Claims (1)

[Claims] 1. A box-shaped paper feed case having an opening, a transport mechanism for loading the paper feed case and transporting paper from the paper feed case, and an image printed on the paper transported by the transport mechanism. And a sensor mechanism for detecting a detection portion of the paper loaded in the paper feed case, the printer being provided with a printing mechanism.