JPS6137457A - Paper-feed controller for printer - Google Patents

Abstract

PURPOSE:To feed paper positively, and to prevent stacked printing by continuously transmitting excitation signals over an electromagnet during a time until the reception of a paper-feed detecting signal from a paper-feed detecting mechanism after the input time of a paper-feed command signal. CONSTITUTION:When a signal such as a paper-feed command one to both printing paper 27 is inputted from a host computer 2, paper-feed flags 1 for flag regions ROM4, RAM6 are set to ''1'' while an excitation signal (a) is transmitted over each electromagnet 12 for several paper-feed mechanism 9, and conduction is started to respective electromagnet 12. Each crank arm 16 is operated, and conduction to several electromagnet 12 is interrupted at times when paper-feed detecting signals (b) at an H level from respective photosensor 30 are received, thus completing the operation of the paper-feed. When the paper-feed detecting signals (b) are not inputted positively though times when the paper-feed detecting signals (b) from each photosensor 30 are inputted are displaced, the excitation signal (a) from the electromagnet of interest 12 is not interrupted, thus resulting in secure paper-feed.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a paper feed detection method for detecting that paper has actually been fed after receiving a paper feed command signal. 11, the present invention relates to a paper feed control device for a printer that reliably executes paper feed when a paper feed command signal is input.

[Prior Art] In general, a printer incorporated in an information processing system receives a character code signal output from a host computer of the information processing system, and prints the type on the print wheel or the character generator that corresponds to the character code. It is configured to read out the dot pattern and use a print head mounted on a carriage to print out the corresponding characters on a print sheet set on a platen. and,
When a paper feed command signal is input from the host computer for a line feed or the like, the paper feed mechanism operates to feed the printing paper by one line.

[Problems to be Solved by the Invention] However, as described above, the paper feed control device for a printer that operates a paper feed mechanism to feed paper in response to a paper feed command signal from a host computer has the following problems. There was a problem. That is, the above assembly feeding mechanism incorporates a large number of electronic members that are movable by a current of a certain level or more, such as an electromagnetic single paper feeding motor that operates in response to a paper feeding command signal. Therefore, even if a paper feed command signal is input from the host computer, the power supply voltage may drop for some reason, causing the movable electronic components mentioned above to malfunction, and paper feeding may not actually be executed. . However, since the control circuit that does not involve driving operates normally for some voltage drop, the paper feed signal is normally received. Then, the host computer determines that the paper has been properly fed and sends a print command for the next line.

As a result, two lines of characters are printed overlappingly on one line.

Also, after a paper feed command signal is input from the host computer, several paper feed mechanisms operate to actually print.

If a power outage occurs in this printer before the paper is fed, the paper will not be fed.

However, since the host computer has once sent the paper feed command signal, the printer naturally determines that paper feed has been executed. After the power is restored, a print command signal for the next line is sent. As a result, 1
Two lines of characters will be printed overlapping each other.

The present invention has been made based on the above circumstances, and its purpose is to detect that paper feeding has actually been carried out and to detect paper feeding in response to a paper feeding command signal from the outside. To provide a paper feed control device for a printer that can reliably execute paper feed even if paper is not fed, prevents overprinting, and improves reliability.

[Means for solving the problem] The present invention drives a crank arm using an N magnet excited in response to a paper feed command signal, and uses this crank arm to drive a ratchet wheel connected to a paper feed roller. A paper that detects that the printing paper set on the paper feed roller has actually been fed in a paper feed control device of a printer that feeds the printing paper set on the paper feed roller one line by rotating the paper. A feed detection fJ4r4 is provided to continuously send an excitation signal to the electromagnet from the input time of the paper feed command signal until the paper feed detection mechanism receives the paper feed detection signal.

[Effect]

If the printer assembly feed control device has this configuration,
After the paper feed command signal is input, the excitation signal to the electromagnet will not be stopped unless the paper feed detection mechanism that detects that the paper feed is actually executed sends out the paper feed detection signal.
Paper feeding is always executed.

[Actual M 1 row J An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a schematic configuration of a paper feed control device according to an embodiment, and reference numeral 1 in the figure indicates a CP (J ( (central processing unit).This CPU1 is
R O stores fixed data such as control programs via a path line 3 consisting of a data bus, an address bus, etc.
M 4 , a RAM 6 which is backed up by the battery 5 during a power outage and temporarily stores various variable data such as flags. I connected to the host computer 2 via the transmission line 7
10 Interface 81 A paper feed drive circuit 10 which sends an excitation signal a in response to a paper feed command signal to the paper feed mechanism 9 and receives a paper feed detection signal from the paper feed mechanism 9.
The control circuit 11 controls the power supply detection circuit 11, etc., which detects power outage and power outage recovery of the control device.

In addition, in the paper feed control device of the embodiment, assuming an electronic cash register, the paper feed mechanism 9 is replaced by two paper feed mechanisms with the same configuration for two printing sheets, a receipt and an internal recording paper. It consists of

FIG. 2 is a schematic diagram showing the schematic structure of each paper feed mechanism 9. As shown in FIG. 12 in the figure indicates that when a paper feed command signal is input from the CPU 1 to the paper feed drive circuit 10, the paper feed drive circuit 10
When this electromagnet 12 is excited, a stop plate 14 pivoted at a fulcrum 13 rotates in the direction of the arrow. When the sleeve plate 14 rotates in the direction of the arrow, the stop shaft 18 of the eccentric cam 17 rotatably attached to the side surface of the crank arm 16 pivotally supported on the fulcrum 15 is removed from the stop plate 14. Then, the eccentric cam 17 rotates clockwise due to the restoring force of the spring 19 connected to the stop shaft 18, and the pinion 2, which is rotationally driven at a constant speed by the printing motor 20, rotates clockwise.
Matches 1. The eccentric cam 17 is then further rotated clockwise by the printing motor 20. Eccentric cam 17
When the crank arm 16 further rotates clockwise, the crank arm 16 rotates counterclockwise about the fulcrum 15, and the paper feed arm 22 pivotally supported on the side surface of the crank arm 16 moves in the direction of the arrow. Then, the claw portion 23 attached to the tip of the paper feed arm 22 rotates the ratchet wheel 25 attached to one end of the shaft of the paper feed roller 24 clockwise by one groove.

When the ratchet wheel 25 rotates clockwise, the printing paper 27 inserted between the paper feed roller 24 and the pinch roller 26 is fed by one line in the direction of the arrow.

At the same time, it is fixed to the crank arm 16 and has a long hole 2 in the center.
The shielding plate 29 with holes 8 moved in the direction of the arrow to the position shown by the dotted line. When the elongated hole 28 drilled in the shielding plate 29 reaches the dotted line position, the elongated hole 28 is inserted into the shielding plate 29 from both sides.
An H-level paper feed detection signal is sent to the paper feed drive circuit 10 from a photosensor 30 consisting of a light emitting diode and a phototransistor that are arranged to sandwich the paper.

Note that when the crank arm 16 remains at the fixed position shown in the figure, the light emitting diode of the photosensor 30 and the phototransistor are shielded by the shielding plate 29, so the output signal is at L level. These shielding plates 29. Long hole 28
．． The photo sensor 30 constitutes a paper feed detection mechanism.

When the eccentric cam 17 further rotates, the crank arm 16
is rotated clockwise in the opposite direction and returned to the position shown in the figure, the eccentric cam 17 is separated from the pinion 21, and the electromagnet 12 is de-energized, so the stop plate 14 comes into contact with the stop shaft 18, and the eccentric cam 17 moves away from the pinion 21. The cam 17 stops at the fixed position shown.

As shown in FIG. 3, the RAM 6 includes a data area RA1 for temporarily storing various data and command signals inputted from the host computer 2 via the transmission path 7 and I10 interface 8, as well as a A paper feed state memory RA2 that stores the operating state (FD, ST) of the mechanism 9 with the code [0]N]. A flag area RA3. is used to store paper feed flags (FE1, FLAG, FE2.FLAG) indicating that a paper feed command signal has been input for each of paper feeds 1 and 9. RA4 is formed.

Note that the operating states FD and S of the paper feeding state memory RA2 are
T [0] indicates the state in which the paper feed command signal has not been input yet or the operating state in which all paper feed operations have been completed, and the operation status fiFD, sT [1] indicates the state in which all paper feed operations have been completed after the paper feed command signal has been input. This shows the operating status until the paper feeding operation is completed.

The CPUI is connected to each printing paper 2 from the host computer 2.
When a paper feed command signal is input to 110 interface 8, the paper feed process is executed according to the flowchart in FIG. The paper feed starts the printing motor 20 of the structure 9. Next, the RAM
The operation state ff1FD, ST of the paper feed mechanism 9 corresponding to the paper feed state memory RA2 of No. 6 is set to [11, and the corresponding flag area RA3.6 is set to [11]. Set the paper feed flag of RA4 to 1. At the same time, the sending of the excitation signal a to the electromagnet 12 of the corresponding paper feed change (Toma 9 is started. As a result, the electromagnet 12
is excited, the paper feed roller 24 rotates, and the printing paper 27
The paper will be advanced by one line.

Then, when it is confirmed that the H level paper feed detection signal indicating that the paper feed was actually executed from the photosensor 30 is input to the paper feed drive circuit 10 at Pl, this H level paper feed detection signal indicating that paper feed has actually been executed is confirmed.
Flag area RA4 corresponding to the level paper feed detection signal
Or clear the paper feed flag of RA5 to O. at the same time,
The excitation signal a sent to the electromagnet 12 is cut off. Electromagnet 1
When power supply to 2 is stopped, it is checked in P2 whether all paper feed flags have been cleared to O. If there is a paper feed flag that is still set to 1, paper feed 11 (M9 is determined to exist, and P
From the photosensor 30 of 9 to the tassel feeder 4 to H
Check whether the level paper feed detection signal is sent. If all paper feed flags are cleared to O at P2, it is determined that all paper feed operations in response to the paper feed command signal input from the host computer 2 have been completed, and the paper feed state memory RA2 is The operating states FD and ST are cleared to O and this paper feeding process is completed.

FIG. 5 is a flowchart showing the startup process when the paper feed control device is powered on. That is, when the operator turns on the power or the power supply detection circuit 11 detects a power failure recovery, the normal initial processing is executed first, and then each operating state FD of the paper feeding state memory RA2 in the RAM 6 backed up by the battery 5 is stored.
, check the value of ST. And all operating states FD, S
T is.

If it is [0], it is determined that there is no power outage during the paper feeding operation, and normal work is executed. In addition, the operating state ff1FD
, If sT is other than [0, it is determined that a power outage occurred during paper feeding operation and all paper feeding operations have not been completed.
The printing motor 20 of the paper feed number 9 is started to rotate. Then, the excitation signal a is sent again to the electromagnet 12 of the paper feed mechanism 9 whose forward feed flag is set to 1, and the corresponding printing paper 2 is
After feeding 7 by one line, the process returns to Pl in FIG.

With the printer paper feed control device configured as described above, as shown in FIG. When a paper feed command signal for, for example, both print sheets 27 is input from the host computer 2 in the flag area RA4. The paper feed flag of RAS is set to 1, and an excitation signal a is sent to each electromagnet 12 of each paper feeder Wi9, and each electromagnet 12 starts being energized. And each crank arm 1
6 operates and receives an H-level paper feed detection signal from each photo sensor 30, each electromagnet 12
The current supply to the paper is cut off, and this paper feeding operation is completed.

Moreover, as shown in the figure, even if the input times of the paper feed detection signals from each photosensor 3o are shifted, the excitation signal a of the corresponding electromagnet 12 will not be cut off unless the paper feed detection signal @b is input. , paper feeding is always executed.

With such a paper feed control device, there is a phenomenon in which paper feed is not actually executed even though a paper feed command signal is input from the host computer 2 due to some factor such as a voltage drop in the power supply while the power is on. This eliminates the problem of overlapping characters on one line without paper feeding.

In addition, if a power outage occurs between the input of a paper feed command from the host computer 2 and the actual completion of the paper feed operation, and the power is restored after a certain period of time, the paper feed state memory RA2 in the RAM 6 will be affected. The operating state immediately before the power failure is determined based on the stored contents of the states FD and ST, and the paper feeding operation is executed. Therefore, even if a power outage occurs during a paper feeding operation, the paper will be normally fed when the power is restored, so that characters will not be printed out in a single line.

In this way, paper feeding can be reliably executed in response to the input paper feeding command signal, and the reliability of the printer can be improved.

Note that the present invention is not limited to the embodiments described above. In the practical example, we have explained the case where there are two paper feeders that feed two types of printing paper, the receipt and the internal recording paper built into the electronic cash register, but there is a single paper feeding mechanism for printing paper. The number of installations is not particularly limited.

[Effects of the Invention] As explained above, according to the present invention, by detecting that paper feeding is actually performed, even if paper feeding is not performed in response to a paper feeding command signal from the outside, Paper can be fed reliably, preventing overprinting,
The reliability of the entire paper feeding device can be improved.

[Brief explanation of the drawing]

The figure shows a paper feed control device for a printer according to an embodiment of the present invention, and FIG. 1 is a block diagram schematically showing a 4M configuration;
Fig. 2 is a schematic diagram showing the general configuration of the paper feeding mechanism, Fig. 3 is a diagram showing the main memory of the storage section, Figs. 4 and 5 are flow charts showing the operation, and Fig. 6 is a time diagram showing the operation. It is a chart. 1...CPtJ, 2...Host computer, 6.
...RA IV+, 8...I10 interface,
9...Paper feed mechanism, 10...Paper feed drive circuit, 11
...Power supply detection circuit, 12...Electric power supply, 14...
Sl-Brim plate, 16... Crank arm, 17...
Eccentric cam, 20... Print motor, 21... Binion, 22... Paper feed arm, 25... Ratchet wheel, 24... Paper feed roller, 27... Print paper,
29... Shielding plate, 30 Photo sensor, RA2... Paper feed state memory, RA3. RA4...Flag area. Applicant's representative Patent attorney Takehiko Suzue Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] A crank arm is driven by an electromagnet excited in response to a paper feed command signal, and the crank arm is used to rotate a ratchet wheel connected to the paper feed roller. A paper feed control device for a printer that feeds print paper by one line includes a paper feed detection mechanism that detects whether the print paper set on the paper feed roller is actually fed, and a paper feed detection mechanism that detects the paper feed command signal. A paper feed control device for a printer, comprising means for continuously sending an excitation signal to the electromagnet from an input time until receiving a paper feed detection signal from the paper feed detection mechanism.