JP2002254780A - Printer control device and printer control method - Google Patents

Abstract

[PROBLEMS] To provide a printer control apparatus and a printer control method capable of reliably and accurately detecting a double feed in which a plurality of print sheets are fed and fed while overlapping a plurality of print sheets. . A printer control device and a printer control method according to the present invention measure a paper feed amount from a time when an upper end of a print sheet is detected at a predetermined position to a time when a lower end is detected, and convert the amount into a print paper page length. And, as a result of comparing the converted print paper page length with the print paper page length on the data, the converted print paper page length exceeds a predetermined allowable range and is larger than the print paper page length on the data. Sometimes,
This is detected as a double feed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer control apparatus and a printer control method, and more particularly to a method and apparatus for detecting a double feed in which a plurality of printing paper sheets are fed and fed while being overlapped with each other, with high accuracy. The present invention relates to a printer control device and a printer control method which enable the printer control. Further, the present invention relates to a recording medium on which a computer program for executing the printer control method is recorded.

[0002]

2. Description of the Related Art In a general printer which has been widely used at present, printing paper set in a tray is fed one by one by a paper feeding motor and fed, and the paper is fed into the printer by a paper feeding motor to perform printing. Things.

At the time of paper feeding, various measures have been taken to ensure that the printing paper is fed out one sheet at a time. Nevertheless, a plurality of printing papers still overlap due to static electricity between the printing papers. Double feed, in which the paper is fed and fed as it is, may occur.

In the conventional printer control apparatus and printer control method, double feed is detected by detecting a jam including a jam (paper jam). More specifically, when the lower end of the printing paper cannot be detected by feeding a predetermined amount of paper, for example, 22 inches (1 inch = 2.54 cm) after the start of the paper discharging operation, the jam occurs. Judgment and detection were performed.

[0005]

However, in the conventional printer control apparatus and printer control method, since the double feed is detected as a kind of jam, a considerable amount of paper feed is required after the discharge operation is started. When the lower end of the printing paper cannot be detected even if only the paper is fed, the detection as the jam is performed for the first time.

Therefore, for example, when two sheets of printing paper are overlapped with a slight shift and are overlapped, it is very difficult to detect the double feeding by the conventional printer control device and printer control method. Was.

In particular, if double feeding occurs during the execution of double-sided printing, the printed pages on the front and back sides are shifted, and all the printing paper after the printing paper on which double feeding occurred is wasted.
This problem has become a significant problem that cannot be ignored with the spread of printers having a duplex printing function.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to be able to reliably and accurately detect a double feed in which a plurality of print sheets are fed and fed while overlapping. And a printer control method.

[0009]

According to the printer control device of the present invention, the length of the printed paper is measured by measuring the paper feed amount from the detection of the upper end of the print paper at the predetermined position to the detection of the lower end of the print paper. And, as a result of comparing the converted print paper page length with the print paper page length on the data, the converted print paper page length exceeds the predetermined allowable range and exceeds the print paper page length on the data. If the value is large,
It is characterized in that it is detected as a double feed, and a very small value can be set as the predetermined allowable range, so that the double feed can be detected reliably and with high accuracy.

The paper feed amount is determined by counting the number of output pulses of an encoder for converting the drive amount of the paper feed motor into a pulse signal from the time when the upper end of the printing paper is detected at a predetermined position until the time when the lower end is detected. It may be measured as the number of steps.

According to the specific configuration of the printer control device according to the present invention, the number of output pulses of the encoder for converting the driving amount of the paper feed motor into a pulse signal is determined after the upper end of the printing paper is detected at a predetermined position. By counting until the lower end is detected, a paper feed step number counter for counting the number of paper feed steps, and a counted paper feed step number,
The number of steps / page length conversion unit to be converted into the printing paper page length, which is the length of the printing paper in the paper feed direction, and the converted printing paper page length is compared with the printing paper page length in the data, and the converted printing paper When the page length exceeds a predetermined allowable range and is larger than the print paper page length on the data, a page length comparison unit that detects double feed and transmits a double feed notification signal is provided. It is characterized by.

In a specific configuration of the printer control device according to the present invention, it is assumed that the printer control device further includes a multi-feed operation instruction unit for instructing a predetermined multi-feed operation in response to the multi-feed notification signal. Good.

Preferably, the paper feed step number counter, the step number / page length conversion section, the page length comparison section, and the double feed correspondence operation command section are constituted by one arithmetic processing unit.

The upper and lower ends of the printing paper may be detected by a paper detection sensor disposed at the predetermined position.

The page length comparing section compares the converted print page length data to be compared with the converted print page length data at the start of printing or after the start of printing until the lower end of the print sheet is detected. It is good to receive it.

Preferably, the print paper page length data includes a recording medium in which the print data is stored, and is transmitted from a host computer connected to a printer.

The print paper page length data may be data on the length in the paper feed direction of a print paper of a standard selected based on the contents of the print data to be printed.

According to the printer control method of the present invention,
The paper feed amount from the detection of the upper end of the printing paper to the detection of the lower end of the printing paper at a predetermined position is measured and converted into the printing paper page length, and the converted printing paper page length is used as the printing paper page length in the data. When the converted printing paper page length exceeds a predetermined allowable range and is larger than the printing paper page length on the data as a result of the comparison, it is detected as a double feed, and the predetermined printing paper page length is detected. Since a very small value can be set as the allowable range, the double feed can be detected reliably and with high accuracy.

The paper feed amount is determined by counting the number of output pulses of an encoder for converting the drive amount of the paper feed motor into a pulse signal from the time when the upper end of the printing paper is detected at a predetermined position until the lower end is detected. It may be measured as the number of steps.

According to the specific configuration of the printer control method according to the present invention, the number of output pulses of the encoder for converting the driving amount of the paper feed motor into a pulse signal is changed after the upper end of the printing paper is detected at a predetermined position. By counting until the lower end is detected, a paper feeding step number counting process for counting the number of paper feeding steps, and a counted paper feeding step number,
The number of steps / page length conversion process, which is converted into the printing paper page length, which is the length of the printing paper in the paper feed direction, and the converted printing paper page length is compared with the printing paper page length in the data, and the converted printing paper is converted. A page length comparison step of detecting a double feed and transmitting a double feed notification signal when the page length exceeds a predetermined allowable range and is greater than the print paper page length on the data. It is characterized by.

In the specific configuration of the printer control method according to the present invention, it is assumed that the printer control method further includes a multi-feed operation commanding step of instructing a predetermined multi-feed operation in response to the multi-feed notification signal. Good.

The printing paper page length data may be data on the length in the paper feeding direction of a printing paper of a standard selected based on the contents of the printing data to be printed.

According to a recording medium of a computer program of the present invention, a computer program for executing the above-described printer control method of the present invention in a computer system is recorded.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a schematic configuration and a control method of an ink jet printer to which a printer control device and a printer control method according to the present invention are mainly applied will be described.

FIG. 6 is a block diagram showing a schematic configuration of the ink jet printer.

The ink jet printer shown in FIG.
A paper feed motor (hereinafter also referred to as a PF motor) 1 for feeding paper, a paper feed motor driver 2 for driving the paper feed motor 1, and a head 9 for discharging ink onto the printing paper 50 are fixed. And a carriage motor (hereinafter also referred to as a CR motor) 4 for driving the carriage 3 and a CR motor driver 5 for driving the carriage motor 4. A DC unit 6 for issuing a DC current command value to a CR motor driver 5, and a pump motor 7 for controlling ink suction for preventing clogging of a head 9.
And a pump motor driver 8 for driving the pump motor 7
A head driver 10 for driving and controlling the head 9, a linear encoder 11 fixed to the carriage 3, and a linear encoder 1 having slits formed at predetermined intervals.
1 code plate 12, a rotary encoder 13 for the PF motor 1, a paper detection sensor 15 for detecting the end position of the paper being printed, and a CP for controlling the entire printer.
U16, a timer IC 17 for periodically generating an interrupt signal to the CPU 16, and an interface unit (hereinafter, I / O) for transmitting and receiving data to and from the host computer 18.
Also called F. ) 19 and I from the host computer 18
An ASIC 20 that controls the printing resolution, the driving waveform of the head 9, and the like based on the printing information sent via the F19.
And a PROM 21 and a RAM 22 used as a work area and a program storage area of the ASIC 20 and the CPU 16.
And the EEPROM 23, the platen 25 supporting the printing paper 50, and the printing paper 50 driven by the PF motor 1.
, A pulley 30 attached to the rotation shaft of the CR motor 4, and a timing belt 31 driven by the pulley 30.

The DC unit 6 controls the driving of the paper feed motor driver 2 and the CR motor driver 5 based on the control commands sent from the CPU 16 and the outputs of the encoders 11 and 13. Also, the paper feed motor 1 and the CR motor 4
Are all composed of DC motors.

FIG. 7 is a perspective view showing the structure around the carriage 3 of the ink jet printer.

As shown in FIG. 7, the carriage 3 is connected to the carriage motor 4 via a pulley 30 by a timing belt 31, and is driven by a guide member 32 to move parallel to the platen 25. On the surface of the carriage 3 facing the printing paper, a recording head 9 having a nozzle array for discharging black ink and a nozzle array for discharging color ink is provided. Each nozzle receives ink supplied from an ink cartridge 34 to perform printing. Prints characters and images by ejecting ink droplets on paper.

In the non-printing area of the carriage 3, a capping device 35 for sealing the nozzle opening of the recording head 9 during non-printing and a pump unit 36 having the pump motor 7 shown in FIG. 6 are provided. Have been. When the carriage 3 moves from the printing area to the non-printing area, the carriage 3 comes into contact with a lever (not shown), and the capping device 35 moves upward to seal the head 9.

When clogging occurs in the nozzle row of the head 9 or when the cartridge 34 is replaced,
When the ink is forcibly ejected from the pump unit, the pump unit is operated while the head 9 is sealed, and the ink is sucked out from the nozzle opening row by the negative pressure from the pump unit. As a result, dust and paper dust adhering in the vicinity of the nozzle opening row are washed, and the air bubbles in the head 9 are discharged to the cap 37 together with the ink.

FIG. 8 is an explanatory diagram schematically showing the configuration of the linear encoder 11 mounted on the carriage 3. As shown in FIG.

The encoder 11 shown in FIG. 8 includes a light emitting diode 11a, a collimator lens 11b, and a detection processing unit 11c. The detection processing unit 11c includes a plurality (four) of photodiodes 11d and the signal processing circuit 1
1e and two comparators 11fA and 11fB.

When a voltage VCC is applied to both ends of the light emitting diode 11a via a resistor, light is emitted from the light emitting diode 11a. This light is converged into parallel light by the collimator lens 11b and passes through the code plate 12. Code plate 1
2, slits are provided at predetermined intervals (for example, 1/180 inch (1 inch = 2.54 cm)).

The parallel light passing through the code plate 12 enters each photodiode 11d through a fixed slit (not shown) and is converted into an electric signal. The electric signals output from the four photodiodes 11d are subjected to signal processing in a signal processing circuit 11e, the signals output from the signal processing circuit 11e are compared in comparators 11fA and 11fB, and the comparison result is output as a pulse. Pulses ENC-A and E output from comparators 11fA and 11fB
NC-B is the output of the encoder 11.

FIG. 9 is a timing chart showing waveforms of two output signals of the encoder 11 at the time of forward rotation and reverse rotation of the CR motor.

As shown in FIGS. 9 (a) and 9 (b), the pulse ENC is applied to both the forward rotation and the reverse rotation of the CR motor.
-A and the pulse ENC-B differ in phase by 90 degrees. When the CR motor 4 is rotating forward, that is, when the carriage 3 is moving in the main scanning direction, FIG.
As shown in FIG. 9B, the phase of the pulse ENC-A is advanced by 90 degrees from the pulse ENC-B, and when the CR motor 4 is rotating in the reverse direction, as shown in FIG.
The encoder 4 is configured such that the phase is delayed by 90 degrees from the pulse ENC-B. One cycle T of the pulse is equal to the slit interval of the code plate 12 (for example, 1/1).
80 inches), which is equal to the time during which the carriage 3 moves through the slit interval.

On the other hand, the rotary encoder 13 for the PF motor 1 has the same configuration as the linear encoder 11 except that the code plate is a rotating disk that rotates in accordance with the rotation of the PF motor 1. Output pulses ENC-A,
Outputs ENC-B. In the ink jet printer, the slit interval of the plurality of slits provided on the code plate of the rotary encoder 13 for the PF motor 1 is 1/180 inch. The paper is fed by 1440 inches.

FIG. 10 is a perspective view showing a portion related to sheet feeding and sheet detection. The position of the paper detection sensor 15 shown in FIG. 6 will be described with reference to FIG. In FIG. 10, the printing paper 50 inserted into the paper feeding slot 61 of the printer 60 is fed into the printer 60 by the paper feeding roller 64 driven by the paper feeding motor 63. The leading end of the printing paper 50 sent into the printer 60 is detected by, for example, an optical paper detection sensor 15. The paper 50 whose leading end is detected by the paper detection sensor 15 is the PF motor 1
Feed roller 65 and driven roller 66 driven by
Paper feed is performed.

Subsequently, printing is performed by dropping ink from a recording head (not shown) fixed to the carriage 3 moving along the carriage guide member 32. When the paper has been fed to a predetermined position, the end of the currently printed printing paper 50 is detected by the paper detection sensor 15. The printing paper 50 on which printing has been completed is transferred to the gear 6 via gears 67A and 67B driven by the PF motor 1.
7C driven by the paper discharge roller 68 and the driven roller 6
9, the paper is discharged from the paper discharge port 62 to the outside. The rotary shaft of the paper feed roller 65 includes a rotary encoder 13.
Are connected.

FIG. 11 is a perspective view showing in detail a portion related to paper feeding of the printer.

Referring to FIGS. 10 and 11, a part of the printer shown in FIG. 10 relating to paper feed will be described in more detail.

When the leading end of the printing paper 50 inserted into the printer 60 through the paper feeding slot 61 of the printer 60 and fed into the printer 60 by the paper feeding roller 64 is detected by the paper detecting sensor 15, the small gear 87 is driven by the PF motor 1. (Smap) shaft 8, which is the rotation axis of the large gear 67a driven through the
3 and a driven roller 66 provided at the leading end of the holder 89 that presses the printing paper 50 sent from the paper feeding side downward in the paper feeding direction. As a result, the printing paper 50 is fed.

The PF motor 1 is fixed to a frame 86 in the printer 60 by screws 85, a rotary encoder 13 is disposed at a predetermined position around the large gear 67a, and is a rotating shaft of the large gear 67a. Smap axis 83
Is connected to a rotary encoder code plate 14.

The printing paper 50 fed by the paper feeding roller 65 and the driven roller 66 passes over a platen 84 that supports the printing paper 50, and has a small gear 87 and a large gear 67.
a, a discharge roller 68 driven by the PF motor 1 via the intermediate gear 67b, the small gear 88, and the discharge gear 67c.
Then, the paper is fed while being pinched by a toothed roller 69 which is a driven roller, and the paper is discharged from the paper discharge port 62 to the outside.

While the printing paper 50 is supported on the platen 84, the carriage 3 moves left and right in the space on the platen 84 along the guide member 32, and a recording head (not shown) fixed to the carriage 3 ), The ink is ejected to perform printing.

Hereinafter, an embodiment of a printer control device and a printer control method according to the present invention and a recording medium storing a computer program for executing the printer control method will be described with reference to the drawings.

According to the printer control device and the printer control method of the present invention, the paper feed amount from the detection of the upper end of the printing paper at the predetermined position to the detection of the lower end thereof is measured and converted into the printing paper page length. Further, the converted print paper page length is compared with the print paper page length on the data.

As a result of the comparison, when the converted printing paper page length exceeds the predetermined allowable range and is larger than the printing paper page length in the data, it is detected as a double feed.

Since a very small value can be set as the predetermined allowable range set for the detection of the double feed, the double feed can be detected reliably and with high accuracy.

FIG. 1 is a block diagram showing the configuration of a printer control device according to the present invention.

The printer control device according to the present invention counts the number of output pulses of the encoder for converting the driving amount of the paper feed motor into a pulse signal from the time when the upper end of the printing paper is detected at a predetermined position until the time when the lower end is detected. By doing this, a paper feed step number counter 1 for counting the number of paper feed steps
01, a step number / page length conversion unit 102 for converting the counted number of paper feed steps into a print paper page length which is the length of the print paper in the paper feed direction, and printing the converted print paper page length on data. Compared with the paper page length, if the converted print paper page length exceeds the predetermined allowable range and is greater than the print paper page length on the data, it is detected as a double feed and a double feed notification signal is transmitted. The apparatus includes a page length comparing unit 103 and a multi-feed operation instruction unit 104 for instructing a predetermined multi-feed operation in response to the multi-feed notification signal.

The paper feed step number counter 101 is connected to an encoder 13 attached to the paper feed motor (PF motor) 1. The paper feed step number counter 101 is also connected to a paper detection sensor 15 that detects the upper and lower ends of the print paper.

The page length comparison unit 103 converts print page length data to be compared with the print page length converted from the number of paper feed steps at the start of printing or after printing.
Received before the lower end of the print paper is detected. The printing paper page length data is data on the length of the printing paper of a standard selected based on the content of the printing data to be printed, that is, the length of the printing paper used for printing in the paper feeding direction. Since the comparison of the page length is performed after the detection of the lower end of the printing paper, the printing paper page length data may be received until the lower end of the printing paper is detected even after the start of printing. Note that the print paper page length data is transmitted from a host computer connected to a printer and having a built-in recording medium storing print data.

The paper feed step number counter 101, the step number / page length conversion unit 102, the page length comparison unit 103, and the multi-feed handling operation command unit 104 comprise one arithmetic processing unit 1.
00.

FIG. 2 is an explanatory view schematically showing a state in which printing paper is multi-fed.

In the printer, as shown in FIG.
The printing paper 50 set in the tray 90 is
When the printing paper 50 is fed out one by one, the upper end of the printing paper 50 is detected by the paper detection sensor 15. Then, the printing paper 50
Is fed by a paper feed roller 65 and a driven roller 66, and printing is performed on the platen 84 by ink ejected from the print head 9.

When printing progresses to the vicinity of the lower end of the printing paper 50 and the printing paper 50 is sequentially fed, the printing paper 50 does not exist on the paper detection sensor 15 at a certain point in time. Is detected.

Accordingly, the paper feed amount from the detection of the upper end of the printing paper 50 to the detection of the lower end thereof, ie, the number of paper feeding steps, is equal to the length of the printing paper in the paper feeding direction. Yes, it is.

On the other hand, as described above, double feed may occur in which two or more printing papers are fed out while overlapping due to static electricity between the printing papers. In such a case, two or more printing papers may be fed. In many cases, the paper is fed in a state where the upper end and the lower end are not aligned, but are shifted to some extent in the process of feeding and feeding the paper.

For example, as shown in FIG. 2, when two printing papers 50 are fed with a certain amount of deviation, the length from the upper end of one printing paper to the lower end of the other printing paper is reduced. The corresponding number of paper feed steps is measured as the number of paper feed steps from when the upper end of the printing paper 50 is detected to when the lower end is detected.

Therefore, the number of paper feeding steps from the detection of the upper end of the printing paper 50 to the detection of the lower end thereof is measured and converted into the printing paper page length, and compared with the printing paper page length in the data. As a result of the comparison, when the converted printing paper page length is a value larger than the printing paper page length on the data beyond the predetermined allowable range, it can be determined that the multifeed has occurred.

The printer control device and the printer control method according to the present invention detect the occurrence of double feeding based on such a principle.

FIG. 3 is a flowchart showing the operation of the printer control device according to the present invention, that is, the procedure of the printer control method according to the present invention.

Hereinafter, the operation of the printer control device according to the present invention, that is, the procedure of the printer control method according to the present invention will be described with reference to FIGS. Reference is made to other drawings as appropriate.

A recording medium storing print data is built-in, and is selected based on the contents of the print data to be printed according to a print start operation by a host computer connected to the printer (step S1). Length data in the paper feed direction of standard printing paper, that is,
The printing paper page length data is transmitted from the host computer, and the page length comparing unit 103 receives the printing paper page length data (step S2). The print paper page length data is held in the page length comparison unit 103 until a series of print control operations is completed. This print paper page length data is used for comparing the page lengths described later. Since the comparison of the page lengths is performed after detecting the lower end of the print paper, the print paper page length data is used after the start of printing. May be received before the lower end of the printing paper is detected.

On the other hand, when the print data transmitted from the host computer is received by the printer in response to the print start operation (step S3), the print paper 50 is fed out of the tray 90 by the paper feed roller 64, and is fed into the printer. Is fed (step S4).

When the printing paper 50 is further fed into the printer and the upper end of the printing paper 50 is detected by passing the upper end of the printing paper 50 over the paper detection sensor 15 (step S5), the number of paper feeding steps is determined. Is started (step S6). Specifically, when the paper feed step number counter 101 receives a signal indicating that the upper end of the printing paper 50 has been detected from the paper detection sensor 15, the paper feed step number counter 101 outputs the number of output pulses of the encoder 13, that is, The counting of the number of paper feed steps is started.

The counting of the number of paper feeding steps is continued until the lower end of the printing paper is detected, and ends when the lower end of the printing paper is detected (step S7). Specifically, the printing paper 5
The signal indicating that the lower end of the zero is detected is output to the paper detection sensor 15.
, The paper feed step number counter 101 receives the output pulse number from the encoder 13, that is, finishes counting the paper feed step number.

After the counting of the number of paper feed steps is completed, the step number / page length conversion unit 102 converts the counted number of paper feed steps into a print paper page length (step S).
8). For example, when the paper feed resolution is 1/720 inch (1 inch = 25.4 mm) and the page length of the printing paper is calculated in millimeter (mm) units, the quotient obtained by dividing the number of counted steps by 720 When multiplied by 25.4, the number of paper feed steps is converted to a printed paper page length in millimeters.

After the above conversion, the converted printing paper page length is
Compare with the print paper page length on the data (step S
8).

By comparing the page lengths, it is determined whether or not the converted printing paper page length exceeds a predetermined allowable range and is larger than the printing paper page length on the data, that is, whether double feed has occurred. Determine whether or not. Here, assuming that the predetermined allowable range is 5 mm, the comparison and determination of the page length is based on whether the inequality {(converted page length)> (printed paper page length on data) +5 mm} is satisfied. Is equivalent to determining (step S10).

The value of the predetermined allowable range can be set arbitrarily. For example, when the printing paper is A4 standard printing paper, the size is 294 mm in height and 210 mm in width,
A variation of about ± 1 mm in both the vertical and horizontal directions is allowed.
Therefore, if the variation in the size of the printing paper is within a range that is not erroneously detected as a double feed, the predetermined allowable range is:
It can be set as small as possible.

In the prior art, when the lower end of the printing paper cannot be detected by feeding a considerable amount of paper, for example, only 22 inches after the start of the paper discharging operation, the jam is detected for the first time. Compared to what was done,
It is apparent from this numerical value setting that the printer control device and the printer control method according to the present invention can detect double feed reliably and with high accuracy.

If the above inequality expression is not satisfied, it is determined that double feed has not occurred, and the operation and procedure of double feed detection are terminated. When printing the subsequent pages,
While discharging the printing paper currently being printed,
It is preferable to return to step 4 and repeat the operation and procedure after the supply of the printing paper for the subsequent page.

On the other hand, if the above inequality is satisfied, the converted paper page length exceeds the predetermined allowable range and is larger than the data paper page length. Judgment is made, the page length comparing unit 103 detects double feed, and transmits a double feed notification signal for notifying the occurrence of double feed (step S11).

The double feed corresponding operation command unit 104 instructs a predetermined double feed corresponding operation in response to the double feed notification signal.
The instructed multi-feed operation is performed (step S12). The double feed handling operation performed here is, for example, interrupting printing and instructing to reset printing paper, or stopping printing. Alternatively, the multi-feed notification signal may be transmitted to the host computer so that the occurrence of the multi-feed and an instruction to reset the printing paper may be displayed on the display device of the computer.

As described above, the printer control device and the printer control method according to the present invention measure the paper feed amount from the detection of the upper end of the printing paper at the predetermined position to the detection of the lower end of the printing paper, and The converted print paper page length is compared with the print paper page length on the data, and as a result, the converted print paper page length exceeds the predetermined allowable range and is larger than the print paper page length on the data. When the value is a value, it is detected as a double feed, and it is possible to set a very small value as a predetermined allowable range.
Double feed can be detected reliably and with high accuracy.

FIG. 4 is an explanatory diagram showing a recording medium on which a computer program for executing the printer control method according to the present invention is recorded, and an external configuration of a computer system using the recording medium. FIG. 3 is a block diagram showing a configuration of the computer system shown in FIG.

The computer system 70 shown in FIG.
Is a computer main body 71 housed in a mini-tower type housing or the like, and a display device 72 such as a CRT (Cathode Ray Tube), a plasma display, a liquid crystal display device, or the like.
, A printer 73 as a recording output device, a keyboard 74a and a mouse 74b as input devices, a flexible disk drive device 76, and a CD-ROM drive device 77. FIG. 5 is a block diagram showing a configuration of the computer system 70. An internal memory 75 such as a RAM (Random Access Memory) and a hard disk drive unit 78 etc. An external memory is further provided. A recording medium on which a computer program for executing the printer control method according to the present invention is recorded is used in the computer system 70. As the recording medium, for example, a flexible disk 81 and a CD-ROM (Read Only Memory) 82 are used. In addition, an MO (Magneto Optical) disk, a DVD (Digital Versatile Disk), other optical recording disks, and a card memory Alternatively, a magnetic tape or the like may be used.

[0081]

According to the printer control device and the printer control method of the present invention, the paper feed length from the detection of the upper end of the printing paper to the detection of the lower end of the printing paper at a predetermined position is measured to determine the length of the printing paper page. As a result of comparing the printed paper page length with the printed paper page length in the data,
When the converted printing paper page length exceeds the predetermined allowable range and is larger than the printing paper page length on the data, it is determined that the multi-feed is detected, and the predetermined allowable range is very small. Since the value can be set, the double feed can be detected reliably and with high accuracy.

According to the recording medium of the computer program of the present invention, a computer program for executing any of the above-described printer control methods in a computer system is recorded. By executing any of the above in a computer system, the same effect as described above can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a printer control device according to the present invention.

FIG. 2 is an explanatory diagram schematically showing a state in which printing paper is multi-fed.

FIG. 3 shows the operation of the printer control device according to the present invention, that is,
5 is a flowchart illustrating a procedure of a printer control method according to the present invention.

FIG. 4 is an explanatory diagram showing an external configuration of a recording medium on which a program for executing a printer control method according to the present invention is recorded and a computer system using the recording medium.

FIG. 5 is an exemplary block diagram showing the configuration of the computer system shown in FIG. 4;

FIG. 6 is a block diagram illustrating a schematic configuration of an inkjet printer.

FIG. 7 is a perspective view showing a configuration around a carriage 3 of the inkjet printer.

FIG. 8 is an explanatory diagram schematically showing a configuration of a linear encoder 11 attached to a carriage 3.

FIG. 9 is a timing chart showing waveforms of two output signals of the encoder 11 during forward rotation and reverse rotation of the CR motor.

FIG. 10 is a perspective view showing a portion related to paper feeding and paper detection.

FIG. 11 is a perspective view showing a portion related to paper feeding of the printer in detail.

[Explanation of symbols]

 1 Paper feed motor (PF motor) 2 Paper feed driver 3 Carriage 4 Carriage motor (CR motor) 5 Carriage motor driver (CR motor driver) 6 DC unit 6a Position calculator 6b Subtractor 6c Target speed calculator 6d Speed calculator 6e Subtractor 6f Proportional element 6g Integral element 6h Differential element 6j D / A converter 7 Pump motor 8 Pump motor driver 9 Recording head 10 Head driver 11 Linear encoder 12 Code plate 13 Encoder (rotary encoder) 14 Code plate for rotary encoder 15 Paper Detection Sensor 16 CPU 17 Timer IC 18 Host Computer 19 Interface Unit 20 ASIC 21 PROM 22 RAM 23 EEPROM 25 Platen 30 Pulley 31 Timing Belt 32 Guide member of carriage motor 34 Ink cartridge 35 Capping device 36 Pump unit 37 Cap 50 Recording paper 60 Printer 61 Paper feed insertion port 62 Paper discharge port 64 Paper feed roller 65 Paper feed roller 66 Follower roller 67a Large gear 67b Intermediate gear 67c Paper discharge Gear 68 Discharge roller 69 Follower roller (jagged roller) 83 Smap shaft 84 Platen 87 Small gear 88 Small gear 89 Holder 90 Tray 100 Arithmetic processing unit 101 Paper feed step number counter 102 Step number / page length conversion unit 103 Page length comparison unit 104 Double feed operation command section

Claims (15)

[Claims] 1. A method for measuring a paper feed amount from a time when an upper end of a printing paper is detected at a predetermined position to a time when a lower end is detected, converts the measured amount into a printing paper page length, and converts the converted printing paper page length into data. As a result of the comparison with the printed paper page length, when the converted printed paper page length exceeds a predetermined allowable range and is larger than the printed paper page length on the data, it is detected as a double feed. Printer control device. 2. The paper feed amount is obtained by counting the number of output pulses of an encoder that converts the drive amount of a paper feed motor into a pulse signal from the time when the upper end of the printing paper is detected at a predetermined position until the time when the lower end is detected. 2. The printer control device according to claim 1, wherein the number is measured as the number of paper feed steps. 3. A paper feeding step by counting the number of output pulses of an encoder for converting the driving amount of a paper feed motor into a pulse signal from the detection of the upper end of the printing paper at a predetermined position until the detection of the lower end thereof. A paper feed step number counter for counting the number of paper sheets, a step number / page length conversion unit for converting the counted paper feed step number into a print paper page length which is the length of the print paper in the paper feed direction, and a converted print paper The page length is compared with the printed paper page length on the data, and if the converted printed paper page length exceeds a predetermined allowable range and is larger than the printed paper page length on the data, it is detected as a double feed. And a page length comparing unit for transmitting a double feed notification signal. 4. The printer control device according to claim 3, further comprising a multi-feed operation instruction unit for instructing a predetermined multi-feed operation in response to the multi-feed notification signal. 5. The paper feed step number counter, the step number / page length conversion section, the page length comparison section, and the double feed correspondence operation command section are constituted by one arithmetic processing unit. The printer control device according to claim 4, wherein 6. The printer control device according to claim 3, wherein the detection of the upper end and the lower end of the printing paper is performed by a paper detection sensor disposed at the predetermined position. 7. The printing apparatus according to claim 1, wherein the page length comparing section detects the lower end of the printing paper at the time of starting printing or after starting printing the printing paper page length data to be compared with the converted printing paper page length. The printer control device according to claim 3, wherein the printer control device receives the data by a predetermined time. 8. The printer control device according to claim 7, wherein the print paper page length data has a built-in recording medium in which print data is stored, and is transmitted from a host computer connected to a printer. . 9. The printing paper page length data according to claim 1, wherein the printing paper page length data is data on a length in a paper feeding direction of a printing paper of a standard selected based on the contents of the printing data to be printed. Item 9. A printer control device according to any one of Items 3 to 8. 10. A printing paper page length is measured at a predetermined position from a time when the upper end of the printing paper is detected to a time when the lower end is detected, and is converted into a printing paper page length. As a result of the comparison with the printed paper page length, when the converted printed paper page length exceeds a predetermined allowable range and is larger than the printed paper page length on the data, it is detected as a double feed. Printer control method. 11. The paper feed amount is the number of output pulses of an encoder that converts the drive amount of a paper feed motor into a pulse signal.
11. The printer control method according to claim 10, wherein the number of paper feeding steps counted from a time when the upper end of the printing paper is detected at a predetermined position to a time when the lower end is detected is measured. 12. A paper feeding step by counting the number of output pulses of an encoder for converting the driving amount of a paper feed motor into a pulse signal from the detection of the upper end of the printing paper at a predetermined position until the detection of the lower end thereof. Step of counting the number of paper feed steps to count the number, Step of converting the counted number of paper feed steps to the length of the print paper in the paper feed direction / Page length conversion process, and the converted printing The paper page length is compared with the printed paper page length on the data, and if the converted printed paper page length exceeds a predetermined allowable range and is larger than the printed paper page length on the data, it is detected as double feed. And a page length comparing step of transmitting a double feed notification signal. 13. The printer control method according to claim 12, further comprising a multi-feed operation commanding step of instructing a predetermined multi-feed operation in response to the multi-feed notification signal. 14. The printing paper page length data is data on the length in the paper feeding direction of a printing paper of a standard selected based on the content of the printing data to be printed. Item 14. The printer control method according to any one of Items 10 to 13. 15. A recording medium for a computer program, wherein a computer program for executing the printer control method according to claim 10 in a computer system is recorded.