GB2232640A

GB2232640A - Initialising position of continuous stationery in selective printers

Info

Publication number: GB2232640A
Application number: GB9009048A
Authority: GB
Inventors: Shuhei Okamori
Original assignee: Brother Industries Ltd
Current assignee: Brother Industries Ltd
Priority date: 1989-04-24
Filing date: 1990-04-23
Publication date: 1990-12-19
Anticipated expiration: 2010-04-23
Also published as: GB2232640B; GB9009048D0

Abstract

In a selective printer using continuous form stationery, the position on the paper at which printing is started can be adjusted by means on the printer (rather than by reprogramming the format on a host computer), and the correctness of the setting can be established by conducting a test print. As described, a paper sensor is located upstream of the printhead, and the desired head margin can be adjusted up or down the paper by means (e.g. a keypad) associated with the printer. The paper is fed until the sensor first detects the leading edge of the stationery, and is then further fed by an amount calculated to bring the print-start position under the printhead. A test print (composed of a limited number of prints a predetermined character) is then produced. If stationery is correctly positioned, printing may be commenced. If, however, the position is incorrect, the operator enters the required correction (e.g. by means of an up-switch or a down-switch on the keypad). As the paper is already in the paper path, the sensor detects its presence and causes the retraction of the paper until the sensor fails to detect it, and thereafter the paper is reforwarded by the corrected amount. <IMAGE>

Description

Specification Title of the Invention Printing Device Background of the Invention The present invention relates to a printing device capable of employing at least a continuous-form printing sheet, more particularly to a printing device which is equipped with a mechanism for setting the start position of the printing operation at a desired position on the printing sheet.

Conventionally, when setting the print start position to a desired position on a continuous-form printing sheet in this type of printer, the following operation sequence should be conducted. First, while the printing sheet is set in the sheet feed mechanism, by pressing the sheet feed switch, the sheet feed motor is driven so as to feed the printing sheet toward a printing head. In addition, by operating a line feed switch, the sheet is fed pulse by pulse, which is outputted every line feed switch operation, until the print start position on the printing sheet accords with the start position setting mark located near to the print head. When the printer detects that the print start position accords with the setting mark, it receives the print data from the host computer and start printing the data. When the print start position should be adjusted, the printer suspends the print operation and repeats the above operation.

However, with the printer described above, while an operator visually checks the print start position, he or she should press the required switch. Thus, occasionally, the print start position differs from the desired position. It is difficult for the operator to find the most suitable position.

It is therefore an object of the invention to provide an improved printing device capable of setting a print start position from which a printing operation is executed accurately at a printing head by means of a simple operation.

For this purpose, according to the present invention, there is provided a printing device, capable of employing at least a continuous-form printing sheet successively having a plurality of printing forms along a predetermined direction, comprising a printing unit for executing a printing operation on 'the printing sheet, and a sheet feeding unit for feeding the printing sheet along said predetermined direction at least toward a position at which said printing unit is located, said printing device further comprising: print start position setting means for setting a print start position in the printing form from which a printing operation is started; controlling means for controlling said sheet feeding unit so as to feed the printing sheet toward said printing unit; detecting means, provided upstream side of said printing unit in said predetermined direction, for detecting whether a predetermined position on the printing sheet fed toward said printing unit reaches a point at which said detecting means is provided; another controlling means for controlling said sheet feeding unit so as to further fewd the printing sheet till the print start position set by said print start position setting means is located at said printing unit; discriminating means for discriminating whether said predetermined position on the printing sheet is located downstream of said detecting means in said predetermined direction; and third controlling means for controlling said sheet feeding unit so as to reversely feed the printing sheet till said predetermined position on the printing sheet is located upstream of said detecting means when it is discriminated by said discriminating means that said predetermined position is located downstream side of said detecting means.

The invention will be more clearly understood from the following description given by way of example only with reference to the accompanying drawings in which: FIG. 1 is a sectional view showing the principal section of the printing device of the embodiment according to the present invention; FIG. 2 is a structural diagram showing an electronic control unit and a surrounding section of one embodiment of a printing device according to the present invention; and FIGs. 3 and 4 are flow charts showing a print start position setting process employed in the printing device according to the present invention.

Referring to the accompanying drawings, an embodiment of the present invention will be described hereinafter.

FIG. 1 is a sectional view of one side of a principal section of the printing device according to the present invention. In the drawing, in a sheet feed path in a printer frame 1, a platen 2 extended in the breadth direction of the sheet is rotatably supported by a platen shaft 3. At the front, i.e., on the right side of the drawing, of the platen 2, a print head 4 for reciprocatively moving along the platen 2 to print data on a continuous-form printing sheet "P" is disposed. On the downstream side of the platen 2, a sheet guide member 6 for rotatably supporting a plurality of sheet support rollers 5 is disposed along the platen 2. On the other hand, on the upstream side of the platen 2, a cutter 17 for cutting a part of the tractor feed sheet "P" being sent is disposed.

On the upstream side, i.e., the left side of the drawing, of the platen 2 on the feed path of the printing sheet "P", a pair of pin tractors 10, only one side is shown, are disposed. The pin tractors 10 are extended in parallel with the platen 2 and supported on a transfer shaft 11 and a guide shaft 12 rotatably supported to the printer frame 1 so that the movement of the printing sheet "P" can be adjusted in the breadthwise direction. Each of the pin tractors 10 is provided with a drive pulley 13 rotatably associated with the transfer shaft 11 and a follower pulley 14 rotatable on the guide shaft 12, a pin belt 16 with a plurality of pins 15a being rotatably engaged between the drive pulley 13 and the follower pulley 14.

When the transfer shaft 11 is rotated by a sheet feed motor 38, illustrated in FIG. 2, while the feed holes of the printing sheet "P" are engaged with the pins 15a of the pin belt 16, the pin belt 16 is rotatably moved and thereby the feed force is applied to the printing sheet "P" as the pins 15a rotatably move.

The printing device according to the present embodiment is provided with various sensors. Below the sheet guide member 6 upstream of the platen 2, an optical sheet sensor 21 for detecting whether or not the printing sheet "P" is set is mounted on the printer frame 1 by means of a bracket 22. A transparent hole 6a according to the sheet sensor 21 is formed on the sheet guide member 6. The sheet sensor 21 detects whether or not the printing sheet "P" is set via the transparent hole 6a. The sheet sensor 21 also detects the leading edge of the printing sheet "P" which passes on the transparent hole 6a. The position at which the leading edge of the printing sheet "P" is detected by the sheet sensor 21 refers to the reference position.

Besides a power switch, not shown, other various switches are provided. As switches for setting the print start position of the printing sheet "P", which specifically structure the present embodiment, as illustrated in FIG. 2, a test mode switch 24 for entering the print start position setting mode of the printing sheet "P", a run switch 25 for starting this process, an end switch 26 for ending this process, an up switch 27 and a down switch 28 for setting the print start position, an LCD (Liquid Crystal Display) device 29 for displaying the print start position, and so forth are provided.

The detection signals of the above sensors and the output signals from the switches are processed by a signal processing circuit 30. The signal processing circuit 30 is chiefly structured with an electronic control device 36 comprising a known-CPU (Central Processing Unit) 31, a known ROM (Read Only Memory) 32, a known RAM (Random Access Memory) 33, a known input interface 34, and a known output interface 35, the output circuit being provided with a print head drive circuit 37 and a motor drive circuit 39 for driving a sheet feed motor 38.

Referring to FIGs. 3 and 4, the print start position setting process of the printing sheet "P" executed according to the present embodiment will be described, each step being abbreviated as "S" in the following description.

While the printing sheet "P" is set to the printer in a ready position where the leading edge in the sheet feed direction is positioned at the center between the pin tractors 10 and the sheet sensor 21, when the test mode switch 24 is pressed, the setting value of the print start position stored in the RAM 33 is displayed on the LCD device 29. This setting value represents an incremental/decremental value to the reference value stored in the ROM 32. The value is indicated as + N (where N is a positive integer, including 0) on the LCD device 29. The reference value is the driving amount of the sheet feed motor 38 necessary for moving the standard print start position to the position opposed to the print head 4. In other words, the reference value is the drive amount of the sheet feed motor 38 necessary for feeding the printing sheet "P" in the reference position to the position opposed to the print head 4.

To set the print start position of the sheet "P", while observing the setting value displayed on the LCD device 29, the operator operates the up switch 27 and/or down switch 28 when necessary.

Whenever the up switch 27 or down switch 28 is operated, the setting value displayed on the LCD device 29 is incremented or decremented. When this setting value is incremented by 1, the print start position goes away for 1/360 inch from the leading edge of the sheet "P". When this setting value is decremented by 1, the print start position comes close for 1/360 inch to the leading edge. After the setting value becomes the desired value, when the operator presses the run switch 25, the setting value displayed on the LCD device 29 is stored in the RAM 33 as a new setting value and the print start position setting process of the sheet "P" shown in FIG. 3 is executed.

First, in S1, it is determined whether or not the sheet "P" is set according to the detection signal from the sheet sensor 21. When it is determined that the sheet "P" is not set, the process advances to S2. In S2, the setting value of the print start position which is set by the operator is read from the RAM 33 and the driving-amount of the sheet feed motor 38 according to the setting value is added or subtracted to or from the reference value which has been set in advance. In S3, the drive signal for commanding the sheet feed motor 38 to feed the sheet "P" for the driving amount computed in S2 is output. Thus, the pin tractor 10 is started to be drive to feed the sheet "P" and the sheet "P" is further sent from the reference position where the leading edge of the sheet "P" is detected by the sheet sensor 21 in S3-1, and fed to the position where the desired print start position is opposed to the print head 4 in S3-2 based upon the set value having been set in S2. In S4, the test print is executed on the sheet "P" in the position. In the test print operation, a predetermined mark such as " El" or "H" is printed 10 times in succession. With this test print, the print start position can be easily and securely checked at a short time.

In S5, the drive signal is sent to the sheet feed motor 38 so as to feed the sheet "P" till a boundary position between the form on which the predetermined mark is printed and the successive form is located at the cutter 17. The sheet "P" is perforated for each form. With this sheet feed operation, the sheet "P" is fed until the perforated position is opposed to the cutter 17. In the ROM 32, the data, relating to an amount of feeding operation till a first perforation of the sheet "P" is opposed to the cutter 17 after the detection of the leading edge of the sheet "P", are stored in advance. In the RAM 33, a counter for counting a feeding amount of the sheet "P" after the detection is provided. When a counted value of the counter becomes identical with the data having been the above data stored in the ROM 33, the feeding operation of the sheet "P" is ceased. Thus, the first perforation after the detecting operation is opposed to the cutter 17. Further, it may be considered that the sheet "P" is fed in an amount corresponding to length of one form of the sheet "P" after the predetermined printing operation. Thus, the printing operation can be executed from the position corresponding to the set value set at S2 on the successive form.

After the operator manually cuts the sheet "P" by the cutter 17 and he or she determines that the test print marks are printed in the desired positions of the sheet "P", by pressing the end switch 26, the mode is changed to the normal print mode. To change the print start position, the operator uses theup switch 27 and the down switch 28.

When the setting position is changed with the up switch 27 and the down switch 28 and then the run switch 25 is pressed, the process is repeated from S1.

In this state, the sheet "P" is sent to the position where the sheet "P" is opposed to the cutter 17. Thus, since in S1 it is determined that the sheet "P" is set according to the signal from the sheet sensor 21, the process is advanced to S6. In S6, the sheet feed motor 38 is reversely driven and the process for retreating the sheet "P" to an upstream position of the reference position shown in FIG. 4 is executed. In other words, in the processes of S10 and S11 shown in FIG. 4, the drive signal is sent to the sheet feed motor 38 pulse by pulse, the sheet feed motor 38 being reversely rotated, the sheet "P" being retreated until the sheet sensor 21 does not detect the sheet "P". After that, the processes of S2 to S5 are execute. In other words, by repeating the process for computing the driving amount of the sheet feed motor 38 necessary for feeding the position where the desired print start position is opposed to the print head 4 and the test print process, the print start position of the sheet "P" is set to the desired position.

Thus, according to the present embodiment, to check the print start position of the sheet "P", by inputting the desired setting value with the up switch 27 and the down switch 28 and then pressing the run switch 25, the test print operation is executed in the setting position on the sheet "P". After that, the sheet "P" is sent to the position opposed to the cutter 17. Thus, the print position can be checked and the sheet "P" can be cut with simple operations. In addition, since the test print can be executed in a short time, the print start position can be quickly checked.

From the result of the test print, when it is necessary to adjust the print start position once again, by pressing the run switch 25, the sheet "P" is retreated to the reference position. Thus, by pressing the run switch 25, the similar test print is conducted and thereby the print start position can be easily readjusted. In other words, with the simple operations of inputting the print start position and of pressing the run switch 25, the print start position of the tractor sheet "P" can be checked once again.

In addition, according to the present embodiment, when the print start position of the sheet "P" is set, the data according to the setting is stored in the printer. Thus, when another print start position data is newly set, the stored data can be used.

Consequently, it is not necessary to set the start position data from an external host computer and the like, to start the test print, and to conduct complicated operations such as print command operation and sheet feed operation which are necessary when data is not printed in the desired position.

In addition, since it is possible to set the print start position of the sheet "P" on the printer alone, it is not necessary to change the print start position according to each application software package and thereby the operability is improved.

Claims

1. A printing device, capable of employing at least a continuous-form printing sheet successively having a plurality of printing forms along a predetermined direction, comprising a printing unit for executing a printing operation on the printing sheet, and a sheet feeding unit for feeding the printing sheet along said predetermined direction at least toward a position at which said printing unit is located, said printing device further comprising: print start position setting means for setting a print start position in the printing form from which a printing operation is started; controlling means for controlling said sheet feeding unit so as to feed the printing sheet toward said printing unit; detecting means, provided upstream side of said printing unit in said predetermined direction, for detecting whether a predetermined position on the printing sheet fed toward said printing unit reaches a point at which said detecting means is provided; another controlling means for controlling said sheet feeding unit so as to further feed the printing sheet till the print start position set by said print start position setting means is located at said printing unit; discriminating means for discriminating whether said predetermined position on the printing sheet is located downstream of said detecting means in said predetermined direction; and third controlling means for controlling said sheet feeding unit so as to reversely feed the printing sheet till said predetermined position on the printing sheet is located upstream of said detecting means when it is discriminated by said discriminating means that said predetermined position is located downstream side of said detecting means.

2. The printing device according to claim 1, wherein said predetermined position on the printing sheet comprises a leading edge thereof.

3. The printing device according-to claim 1 or 2 which further comprises print controlling means for controlling said printing unit so as to execute a predetermined printing operation when the print start position set by said print start position setting means is located at said printing unit; and fourth controlling means for controlling said sheet feeding unit so as to feed the printing sheet a predetermined amount when said predetermined printing operation is executed.

4. The printing device according to claim 3, wherein said predetermined amount comprises an amount corresponding to length of one form of the printing sheet.

5. The printing device accordinq to any preceding claim wherein said detecting means comprises an optical sensor capable of sensing an existence of the printing sheet.

6. The printing device according to any preceding claim wherein said print start position setting means includes a display unit for displaying data relating to the print start position set by said print start-setting means.

7. A printing device, capable of employing at least a continuous-form printing sheet successively having a plurality of printing forms along a predetermined direction. comprising a printing unit for executing a printing operation on the printing sheet, and a sheet feeding unit for feeding the printing sheet along said predetermined direction at least toward a position at which said printing unit is located, said printing device further comprising: print start position setting means for setting a print start position in the printing form from which a printing operation is started; discriminating means for discriminating whether a predetermined position on the printing sheet is located upstream of a predetermined point provided upstream side of said printing unit in said predetermined direction; controlling means for controlling said sheet feeding unit so as to feed the printing sheet toward said printing unit when it is discriminated by said discriminating means that said predetermined position is located upstream of said predetermined point, and so as to reversely feed the printing sheet till said predetermined position is located upstream of said predetermined point when it is discriminated by said discriminating means that said predetermined position is not located upstream of said predetermined point; detecting means for detecting whether said predetermined position on the printing sheet being fed by said sheet feeding unit reaches said predetermined point; another controlling means for controlling said sheet feeding means so as to further feed the printing sheet based upon the setting operation of said print start position setting means after the detection of said detecting means till the print start position is located at said printing unit; print controlling means for controlling said printing unit so as to execute a predetermined printing operation when the print start position having been set by said print start position setting means is located at said printing unit; and third controlling means for controlling said sheet feeding unit so as to feed the printing sheet a predetermined amount when said predetermined printing operation is executed.

8. The printing device according to claim 7, wherein said predetermined position on the printing sheet comprises a leading edge thereof.

9. The printing device according to claim 7 or 8 wherein said detecting means detects to existence of said printing sheet, whereby said detecting means detects that said leading edge of said printing sheet reaches said predetermined point in accordance with the detection of said detecting means.

10. The printing device according to claim 9, wherein said discriminating means discriminates that said leading edge is not located upstream of said predetermined point when said detecting means detects the existence of said printing sheet, and that said leading edge is located upstream of said predetermined point when said detecting means does not detect the existence of said printing sheet.

11. The printing device according to claim 7, 8, 9 or 10 wherein said predetermined amount comprises an amount corresponding to length of one form of the printing sheet.

12. The printing device according to any one of claims 7 to 11 which further comprises a cutting member, arranged downstream of said printing unit, for cutting said printing sheet, and wherein said third controlling means controls said sheet feeding unit so as to feed the printing sheet till a boundary position between the form on which said predetermined printing operation is executed and the successive form opposes said cutting member.

13. The printing device according to any one of claims 9 to 12 wherein said third controlling means controls said sheet feeding unit so as to feed the printing sheet toward the downstream side direction in said predetermined amount from said predetermined point after the leading edge of the printing sheet is detected at said predetermined point by said detecting means.

14. Theprinting device according to any one of claims 7 to 13 wherein said detecting means comprises an optical sensor provided at said predetermined point capable of sensing an existence of the printing sheet.

15. The printing device according to any one of claims 7 to 14 wherein said controlling means controls said sheet feeding unit so as to feed the printing sheet toward said printing unit in response to a completion of setting operation of the print start position executed by said print start position setting means.

16. A printing device, capable of employing at least a continuous-form printing sheet successively having a plurality of printing forms along a predetermined direction, comprising a printing unit for executing a printing operation on the printing sheet, and a sheet feeding unit for feeding the printing sheet along said predetermined direction at least toward a position at which said printing unit is located, said printing device further comprising: print start position setting means for setting a print start position in the printing form from which a printing operation is started; controlling means for controlling said sheet feeding unit so as to feed the printing sheet toward said printing unit; detecting means, provided upstream of said printing unit in said predetermined direction, for detecting whether a predetermined position on the printing sheet fed toward said printing unit reaches a point at which said detecting means is provided; and another controlling means for controlling said sheet feeding unit so as to further feed the printing sheet till the print start position.set by said print start position setting means is located at said printing unit.

17. The printing device according to claim 16, wherein said predetermined position on the printing sheet comprises a leading edge thereof, and wherein said detecting means comprises an optical sensor capable of sensing an existence of the printing sheet.

18. The printing device according to claim 16 or 17 which further comprises discriminating means for discriminating whether said predetermined position on the printing sheet is located downstream of said detecting means in said predetermined direction; and third controlling means for controlling said sheet feeding unit so as to reversely feed the printing sheet till said predetermined position on the printing sheet is located upstream of said detecting means when it is discriminated by said discriminating means that said predetermined position is located downstream of said detecting means.

19. The printing device according to claim 16, 17 or 18 which further comprises print controlling means for controlling said printing unit so as to execute a predetermined printing operation when the print start position having been set by said print start position setting means is located at said printing unit; and fourth controlling means for controlling said sheet feeding unit so as to feed the printing sheet a predetermined amount when said predetermined printing operation is executed.

20. The printing device according to claim 19, wherein said predetermined amount comprises an amount corresponding to length of one form of the printing sheet.

21. A printing device constructed and arranged substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

22. A printer including a printing device according to any preceding claim.