JP2545775B2 - Printer using cut sheet paper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Outline] A switch for notifying a change in the ejection position of a sheet in a serial printer in which the ejection position is determined and the sheet is set by detecting the upper end and / or the lower end of the sheet without the control of a host device. By setting this switch, the ejection position changed from the first sheet is calculated and stored, and from the second sheet onward, the sheet is set based on the stored feed amount, and the variation in the length of the sheet and the edge of the sheet are performed. Accumulation of error in detection accuracy is prevented.

[Industrial applications]

The present invention relates to a serial printer that prints using cut sheet paper, and in particular, it is possible to arbitrarily change the ejection position for cut sheet paper without being affected by variations in paper length and paper edge detection accuracy. The present invention relates to a printer that uses cut sheet paper.

With the spread of information processing devices, various printers have been developed and put into practical use. However, among the various printers, cut sheet paper is used, and paper setting is performed without the control of the host device like continuous forms. There is something to print.

For such a serial printer, it is required that the ejection position can be arbitrarily set, and it is required that the ejection position of the first sheet set first and the ejection position of the second and subsequent sheets are the same. ing.

Usually, when such a serial printer determines the set position of the paper, the paper detection signal of a sensor that detects the upper end and the lower end of the paper is used as a reference. However, if the ejection position is arbitrarily changed, it is necessary to position the next sheet only by detecting the lower edge of the sheet.

In this case, the setting position of the next sheet is determined at the time when the lower edge of the sheet is detected based on the sheet length and the feed pitch. However, there are variations in the length of the sheet and variations in the accuracy of detecting the lower edge of the sheet by the sensor, but it is necessary that the ejection position does not shift due to this error.

[Conventional technology]

FIG. 2 is a block diagram showing an example of a conventional serial printer.

The processor 1 operates by reading the program stored in the ROM 3. Print data is sent from the host device through the interface circuit 7. The processor 1 temporarily stores the print data in the RAM 2 and then reads it. When the character code is detected, the character generation circuit 4 reads the corresponding character pattern and stores it in the line buffer area of the RAM 2 for one line.

When the print pattern for one line is stored in the RAM 2, the processor 1 instructs the print head control circuit 5 to read the print pattern and cause the print head 6 to print. At the same time, the space control circuit 8 is controlled to drive the space motor 9 to position the print head 6 at the print position.

When the printing of one line is completed or the line feed code is detected from the print data, the processor 1 controls the line feed control circuit 12 to drive the line feed motor 13 to feed the paper.

The sensor 10 detects the upper and lower edges of the paper and notifies the processor 1 via the input port 11.

 FIG. 3 is a diagram illustrating a conventional paper set.

Cut sheet paper 16 is stored in the hopper 15. Here, in order to supply the sheet to the platen 20, the clutch 17 presses the sheet 16 and rotates to feed the sheet 21. The sheet 21 is, for example, a sensor 10 including a light emitting element 18 and a light receiving element 19.
After the upper end is detected by, it is caught in the platen 20 that rotates in conjunction with the clutch 17.

At this point, the press-contact of the paper on the clutch 17 is released, and the paper 21 is set at a predetermined position. Here, the user rotates the platen 20 to set the paper 21 at a desired ejection position.

As the printing progresses, the paper 21 is fed at a predetermined pitch, and the light receiving element 19 detects the light from the light emitting element 18 again to detect the lower end of the paper, and the processor 1 determines from the paper length and the paper feed pitch. The amount of movement by the user is determined, and the feeding amount of the next sheet is determined.

[Problems to be solved by the invention]

As described above, conventionally, since the lower end of a sheet is detected and the process for determining the feeding amount of the next sheet is executed every time the sheet is supplied, the length of the sheet is used as a reference. There is an error for each sheet, and there is also a detection error in the sensor that detects the lower end of the paper. Further, during operation, for example, an error occurs in the amount of paper transportation due to slipping of the paper during paper transportation. Since the amount of feeding the sheet is determined every time one sheet is fed, the amount of feeding determined based on the feeding of the second sheet is based on the feeding of the first sheet. There is a problem that an error from the determined feeding amount is added, and when many sheets are fed, the error for each time is added to the determined feeding amount.

The present invention was created in view of such problems,
In order to prevent variations in paper length and accumulation of sensor detection errors, when the ejection position set by the user is detected for the first time, the paper feed amount obtained from this ejection position is stored, and subsequent paper is An object of the present invention is to provide a printer that uses cut sheet paper in which the ejection position is always the same so that the printer is set with the stored feeding amount.

[Means for solving problems]

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

In FIG. 1, a switch 23 and an input port 24 are added to FIG. 2, and when the switch 24 is pressed, the processor 1 is notified that the user is operating the platen 20, and the processor 1 is notified of this by the bottom edge of the first sheet. The detection is performed and the amount of feeding the paper is stored in the RAM2. Then, the subsequent set amount is determined based on the amount stored in the RAM 2, and the paper is set at the print position.

[Action]

The processor 1 detects that the user sets a sheet by pressing the switch 23, stores the next sheet feeding amount in the RAM 2, and sets the subsequent sheets with the RAM 2 feeding amount.

〔Example〕

In FIG. 1, the user presses the special switch 23 for changing the launch position from a predetermined position.

The processor 1 receives the push signal of the switch 23 from the input port 24
When it is received via, the standard paper setting position is detected to be changed and stored in RAM2. Then, when the paper is ejected after the printing of the first paper is completed, the length up to the print start point of the first paper is given to the paper length and line feed control circuit 12 by the lower end detection signal obtained from the sensor 10. Line feed motor 13
Calculated from the rotation amount of.

The processor 1 stores the calculation result in the RAM 2, 33 when the second and subsequent sheets are fed out, and when the sensor 10 detects the upper end of the sheet, the processor 1 passes the line feed control circuit 12 based on the feeding amount stored in the RAM 2. The line feed motor 13 is controlled to set the paper at the ejection position set by the user.

That is, the transport distance determined by the physical relative position from the exit of the cut sheet hopper to just below the print head of the printer is (1), the paper length is (L), and the user manually uses the platen knob, etc. If the moved distance is (A) and the distance from the print start position A to the lower edge of the paper is (K), then K = LA, so the distance (K) to the lower edge is detected by detecting the lower edge of the first paper. If it is known, the length A from the upper end of the paper to the print start position is A = LK, and the user can manually find the distance (A) that the paper is moved. Therefore, the feed amount (M) of the paper is the sum of the moved distance (A) and the transport distance (1), and M = 1 + A, and the paper length L becomes irrelevant. This length is stored in the RAM 2, and when the second and subsequent sheets are fed out, this length is read out and control is performed so that the position of the delivery amount (1 + A) is always the ejection position.

When the switch 23 is pressed again, the contents of RAM2 stored in the above operation are erased and the new feeding amount is set to RA again.
Store in M2.

By doing so, the variation in the length of the paper is influenced only by the error of the first paper, and the accumulation can be prevented. Moreover, the detection error of the sensor is not accumulated.

〔The invention's effect〕

As described above, according to the present invention, it is possible to prevent the ejection position set by the user from gradually deviating due to variations in the length of the sheet and accumulation of errors in detecting the lower edge of the sheet.

[Brief description of drawings]

FIG. 1 is a block diagram of a circuit showing an embodiment of the present invention, FIG. 2 is a block diagram showing an example of a conventional serial printer, and FIG. 3 is a diagram explaining a conventional paper set. In the figure, 1 is a processor, 2 is RAM, 3 is ROM, 4 is a character generation circuit, 5 is a print head control circuit, 6 is a print head, 7 is an interface circuit, 8 is a space control circuit, 9 is a space motor, 10 Is a sensor, 11 and 24 are input ports, 12 is a line feed control circuit, 13 is a line feed motor, 15 is a hopper, 16 and 21 are paper, 17 is a clutch, 18 is a light emitting element, 19 is a light receiving element, 20 is a platen, 23 Is a switch.

Claims (1)

(57) [Claims] 1. A printer, which detects an end portion of a sheet to be fed, determines an ejection position, sets the sheet at a printing position, and prints, and a notification means (23, 24) for notifying the ejection position change. When the lower end of the first paper is detected by the notification of the notification means (23, 24), the length from the upper end of the first paper to the print start position is calculated from the paper length and the paper feed amount, and the paper is fed out. A control means (1) for deciding the amount and a storage means (2) for storing the feeding amount of the sheet decided by the control means (1) are provided, and the second and subsequent sheets are the storage means (2). A printer using cut sheet paper, characterized in that it is set at a print start position based on the feeding amount of the paper stored in.