JPH04265771A - Continuous sheet transfer method of printer - Google Patents

Abstract

PURPOSE:To shorten intervals between sheet feeds at the time of continuous transfer of sheets by continuously performing a process wherein a sheet is fed to a printing position or fed thereto in advance and a process for control of the sheet from the change of lines to the delivery of the sheet. CONSTITUTION:A motor 10 is reversely driven to feed a sheet from a hopper 3 through a sheet feed roller 5 and a separation roller 6, then to an inserter roller 7. When the sheet 14 reaches the roller 7, a manual insertion detecting sensor 12 detects the leading end of the sheet to turn the motor 10 in a normal direction, thereby starting an advance feed control. When a position where the printing of the sheet starts has come just under a printing head 2, the advance control is finished, while line feed of the sheet 14 by the roller 7 is performed until the leading end of the sheet leaves the roller 7. As soon as the tailing end of the sheet 14 passes just under the head 2, a delivery action by a delivery roller 9 is started and then finished when the trailing end of the sheet 14 has left the roller 9 and a motor 11 is caused to rotate in a normal direction.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous paper conveyance method for shortening paper feeding intervals and improving throughput when a plurality of sheets of paper are continuously conveyed and printed in a printer.

0002

2. Description of the Related Art FIG. 7 shows an example of a paper conveyance mechanism of a conventional printer. In FIG. 7, 1 is a platen, 2 is a print head, 3 is a hopper, 4 is stacked paper, 5 is a paper feed roller, 7 and 8 are inserter rollers, 9 is an ejection roller, and 14 is paper being fed , 15 and 16 are idle gears, and 17 is a motor.

The print head 2 is mounted on a carriage (not shown) and is configured to move in a direction perpendicular to the paper surface to perform printing. The motor 17 is fed by a belt to the inserter rollers 7 and 8, and is also fed to the paper feed roller 5 and the discharge roller 9 via idle gears 15 and 16. The motor 17 can be driven to rotate in both forward and reverse directions, and is used for each operation stage of feeding paper from the hopper 3, feeding the paper first onto the platen (positioning the printing start position from the leading edge of the paper), feeding a new line, and discharging the paper. Accordingly, the paper feed roller 5, inserter rollers 7 and 8, and discharge roller 9 are rotated by appropriate amounts in respective predetermined directions.

FIG. 8 shows the timing of these paper conveyance controls. When a paper feed command is input from a host (not shown), the motor 17 is first rotated in the reverse direction (counterclockwise) to rotate the paper feed roller 5 in the reverse direction, and feeding of the paper 14 from the hopper 3 is started. let Thereafter, at the timing when the leading edge of the paper 14 reaches the inserter roller 7, the motor 17 is switched to normal rotation (clockwise), and the first-out control of (2) is started.

As shown in ■, when the predetermined position several cm from the leading edge of the paper reaches directly below the print head 2, the advance control ends, printing starts, and as shown in Line feed is performed sequentially, and when the trailing edge of the paper passes the print head 2, the ejection control (2) is started, and when the paper is sent out from the ejection roller 9 at (2), the ejection control is ended. Upon completion of this ejection control, reception of the next paper feed command is started, and when the paper feed command is input, the control from (2) is repeated.

[0006]

[Problems to be Solved by the Invention] In the paper transport mechanism of a conventional printer, feeding of the next paper cannot be started until the preceding paper has been ejected, and each paper is controlled completely in series. , there was a problem that the paper feeding interval became long and the printing process took time. An object of the present invention is to shorten the paper feeding interval during continuous paper transport.

[0007]

[Means for Solving the Problems] The present invention aims to shorten the paper feeding interval by parallelizing the control of each continuously conveyed sheet as much as possible. The first process is to feed the paper to the printing position and perform advance feeding, and the second process is to feed the paper from the printing line feed to ejecting the paper.
The paper feeding process is divided into two processes, each of which can be controlled independently, and the first process and the second process are executed in parallel for two sequential sheets of paper that are continuously conveyed. Significantly shorten the feed interval.

FIG. 1 is an explanatory diagram of the principle of the present invention, and exemplarily shows a paper conveyance mechanism of a printer according to the present invention. In FIG. 1, 1 is a platen. 2 is a print head. 3 is a hopper. 4 is paper stacked in the hopper 3. Reference numeral 5 denotes a paper feed roller that takes out sheets of paper one by one from the hopper 3. Reference numeral 6 denotes a separation roller that relays and feeds the paper taken out by the paper feed roller 5. Reference numeral 7 denotes an inserter roller that feeds the paper to the printing position on the platen 1 and performs advance and feed operations.

Reference numeral 8 denotes an inserter roller that takes over the sheet changing operation performed by the inserter roller 7 from the middle. 9 is a discharge roller. Reference numeral 10 denotes a motor that can rotate in forward and reverse directions and drives the inserter roller 7, separation roller 6, and paper feed roller 5 with a belt. Reference numeral 11 denotes a motor that can rotate in forward and reverse directions and drives the platen 1, inserter roller 8, and discharge roller 9 with a belt. Reference numeral 12 denotes a manual insertion detection sensor that detects when paper is manually inserted.

Reference numeral 13 denotes a first-out detection sensor for detecting the leading edge of a sheet in order to control the first-out position of the sheet. 14 is a sheet of paper that is being fed to the printing position. 14' is a sheet of paper that is being ejected after printing has been completed. Motor 10 and motor 11 are independently controlled, and the feeding of original 14 and original 14' can be controlled in parallel. For example, when the document 14' is ejected from the ejection roller 9,
The original 14 is fed by the inserter roller 8,
On the other hand, if a new paper feed command has been accepted, the paper feed roller 5 has started the operation of feeding the next paper from the hopper 3. In this way, two successive sheets of paper are always fed in parallel.

[0011]

[Operation] The control timing of the paper conveyance mechanism according to the present invention shown in FIG. 1 will be explained using FIG. 2. When a paper feed command is first accepted, operations from ■ to ■ are performed in sequence, and if paper feed commands have been inputted up to ■, the operations following ■' are started in parallel. This will be explained in detail next.

■: The motor 10 is reversed, and a sheet of paper is fed from the hopper 3 by the paper feed roller 5 and is sent to the inserter roller 7 with the help of the separation roller 6. ■: When the paper 14 reaches the inserter roller 7, the leading edge of the paper is detected by the manual insertion detection sensor 12, and the motor 10
can be switched to normal rotation. The inserter roller 7 rotates normally to send out the paper 14 to the right, and first-out control is started. The first-out position is defined as the position where the paper 14 is fed a certain distance after the first-out detection sensor 13 detects the leading edge of the paper 14.

[0013] ■: When the position at which printing on the paper is started is directly below the print head 2, the advance control ends. ■: The line feed of the paper 14 by the inserter roller 7 is
This is continued until the trailing edge of the paper leaves the inserter roller 7. (2): The motor 11 is driven to rotate forward at the timing when the leading edge of the paper 14 touches the platen 1, and the platen 1 and the inserter roller 7 are rotated forward. This continues the line feed for the rest of the paper 14.

■: When the trailing edge of the paper 14 (or 14') passes directly below the print head 2, the ejection roller 9
Start the ejection operation. (2): At the timing when the trailing edge of the paper 14' leaves the discharge roller 9, the discharge operation is terminated and the forward rotation of the motor 11 is terminated.

[0015] In parallel with ■, ■, ■, the next ■', ■', ■'
Execute the action. ■': The motor 10 is driven in reverse to start feeding the next sheet. ■': Drive the motor 10 in normal rotation and start advance control. ■': End first-out control.

[0016]

Embodiment FIG. 3 shows the configuration of a printer control section according to an embodiment of the present invention. In FIG. 3, 18 is a CPU, 19 is a console, 20 is a data storage RAM, 21 is a control program storage ROM, 22 is a paper feed control section, 23 is a line feed control section, 24 is a print control section, and 25 is a paper feed motor. , 26 is LF
(line feed) motor, 27 is CR (carriage) motor,
28 is a print head, 29 is a manual insertion detection sensor, 30 is a first-out detection sensor, and 31 is a host main unit. Paper feed motor 25 and LF motor 26 in FIG. 3 correspond to motor 10 and motor 11 in FIG. 1, respectively.

The CPU 18 executes a control program based on commands from the main unit 31, and instructs the paper feed, line feed, and print control units to drive the motor and print head. Next, control in the case of continuous paper feeding will be explained. Figure 4
shows the flow of paper feeding execution. This flow is executed in response to instructions for paper feeding start and advance start from the flow in FIG. 5, which will be described later. The upper half of the flow shows paper feeding control, and the lower half shows advance control.

When paper feeding is started, the paper feeding motor 25 is rotated in reverse and driven until the manual insertion detection sensor 29 detects the leading edge of the paper and turns on. When the sensor 29 is turned on, the motor 25 is further driven by the distance to the inserter roller 7 in FIG. 1 plus α to complete the paper feeding process.

When the first feed is activated, the paper feed motor 2
5 is rotated in the forward direction and driven until the first out detection sensor 30 detects the leading edge of the paper and turns on. When the sensor 30 is turned on, the motor 25 is further driven by the distance to the print head to perform the first-out termination process.

FIG. 5 is a flowchart of line feed execution. This line feed execution flow performs the main control, and the LF motor 2
The on/off status of the manual insertion detection sensor 29 and first out detection sensor 30 is checked between the line feed drives for 6, and if paper feeding or first out is not being performed, they are activated to enable parallel operation. Line feed feed is done by paper feed motor 25 and L.
Since both of the F motors 26 are involved, in the line feed execution flow, line feed feed control is performed for these two motors. On the other hand, in the sheet feeding execution flow shown in FIG. 4, the sheet feeding motor 25 for sheet feeding and advance feeding is controlled.

First, the number of line feed pulses for one line is set in a counter, and the excitation phase of the LF motor 26 is switched to advance one step in the forward rotation direction. Next, check the hand insertion detection sensor 29, and if it is off and no paper is detected, decrement the number of line feed pulses on the counter by 1, and if the result is 0, repeat the operation of moving the LF motor 26 one step further. .

On the other hand, if the manual insertion detection sensor 29 is on, it is checked whether or not paper feeding has been started, and if it has not been started, paper feeding control according to the flow shown in FIG. 4 is started, and then first out detection is performed. The sensor 30 is checked, and if it is off and the paper has not been fed first, the first feeding control of the flow shown in FIG. 4 is activated, and then the number of line feed pulses is decremented by one. However, the advance detection sensor 30
If it is on and first feeding has been completed, the excitation phase of the paper feed motor 25 is switched, advances by one step, and then the number of line feed pulses is decremented by 1.

[0023] Also, printers may require reverse modification operations. FIG. 6 is an execution flow when this sheet is fed with a reverse line feed. In this case, since the paper is fed in the opposite direction on the platen, there is a possibility that there will be a collision if the next paper is being fed or advanced. is performed, the reverse feed operation is not performed, and only when the next paper feed has not been started, the excitation phase of the LF motor 26 and paper feed motor 25 is switched, and the number of line feed pulses is changed. Execute step feed in the opposite direction by -1.

By the way, in the conventional example shown in FIG. 7, when the paper is fed in the forward direction, the slight difference in the feeding amount of the inserter rollers 7 and 8 before and after the platen 1 causes the paper to be moved toward the print head 2.
There is a disadvantage that the line feed interval is disturbed by the bulge that bulges at the bottom of the paper and disappears when the trailing edge of the paper leaves the inserter roller 7. As a solution to this problem, the diameter of the inserter roller 8 is made larger than the diameter of the inserter roller 7, and the feed amount of the inserter roller 8 is
This prevents bulges from occurring by setting the feed amount to be larger than the feed amount. However, in this case, it becomes a hindrance when a reverse line feed occurs, and the inserter roller 8 must be raised to a free state during a reverse line feed, making the mechanism and control complicated.

However, according to the present invention, the diameters of the inserter rollers 7 and 8 are made the same in FIG. Bulging can be easily prevented by performing the opposite control. For example, when a step motor is used to perform line feed with 60 pulses per line, this can be easily achieved by providing a difference of 3 pulses per 720 pulses between the motors 10 and 11.

[0026]

According to the present invention, since parallel operations are performed during continuous paper feeding, the paper feeding interval is shortened, and throughput can be significantly improved.

[Brief explanation of the drawing]

FIG. 1 is a diagram explaining the principle of the present invention.

FIG. 2 is a control timing diagram illustrating the operation of the present invention.

FIG. 3 is a configuration diagram of a printer control unit according to an embodiment of the present invention.

FIG. 4 is a flow diagram of paper feeding execution according to an embodiment of the present invention.

FIG. 5 is a flow diagram of line feed execution according to an embodiment of the present invention.

FIG. 6 is a flow diagram of performing a reverse line feed according to an embodiment of the present invention.

FIG. 7 is a configuration diagram of an example of a paper conveyance mechanism of a conventional printer.

FIG. 8 is a control timing diagram of a conventional printer.

[Explanation of symbols]

1 Platen 2 Print head 3 Hopper 5 Paper feed roller 7, 8 Inserter roller 9 Discharge roller 10, 11 Motor

Claims (3)

[Claims] 1. A first process of feeding paper to a printing position and first feeding the paper, and a second process from printing line feed to ejecting the paper are provided so as to be independently controllable, and the first process and 2. A continuous paper conveyance method for a printer, characterized in that the second step is executed in parallel for any two continuously conveyed sheets. 2. A first inserter roller and a second inserter roller each driven by separate motors are provided before and after the platen, and the first inserter roller is driven to feed the paper onto the platen and feed it first. control,
Next, the first inserter roller and the second inserter roller are driven to perform printing and line feed control, and when the trailing edge of the paper leaves the first inserter roller, the first inserter roller starts printing the next paper. A method for continuously transporting paper in a printer, characterized by starting first-out control. 3. In claim 2, when feeding paper in the forward direction with a line feed, the paper feeding speed of the second inserter roller is set higher than the paper transporting speed of the first inserter roller in the forward direction, and the paper feeding speed of the second inserter roller is set higher than the paper transporting speed of the first inserter roller in the forward direction. 1. A continuous paper conveyance method for a printer, characterized in that the paper feed speed of a first inserter roller in the opposite direction is made higher than the paper feed speed of a second inserter roller when performing line feed in a direction.