JP2898191B2 - Printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer, and more particularly, to a printer in which a paper feed speed is variable according to a value of a top margin of a paper.

It is desirable that the paper feed speed of a printer is high in order to improve throughput. On the other hand, in order to stop the paper under the print head, it is necessary to secure a deceleration distance for reducing the paper feed speed.

[0003]

2. Description of the Related Art FIG. 8 is an explanatory view of a conventional art, and shows a conventional paper feed system. The sheet 10 is sent from a hopper (not shown) over a guide 18 to a sheet feed roller 19, and is further fed under a print head 16 by a pair of upper and lower sheet feed rollers 19 from a sheet inlet. At this time, between the paper feed roller 19 and the print head 16, the leading end of the paper 10 is detected by the paper detection sensor 60. When the printing is completed, the guide 23 and the sheet discharging roller 24
The paper 10 is discharged onto the stacker 25.

In this case, the sheet 10 is fed at a predetermined sheet feed speed from the hopper through the sheet feed roller 19 until the leading end of the sheet is detected by the sheet detection sensor 60. This paper feed speed is fixed. When the paper 10 is detected, the paper 10 is decelerated at a predetermined rate, and when the first print line reaches below the print head 16, the feeding of the paper 10 is temporarily stopped, and the paper 10 remains at that position. Thereafter, the paper 10 is fed at a speed synchronized with the printing timing.

The distance d1 between the paper detection sensor 60 and the print head 16 is the deceleration distance D. Within this distance D, that is, triggered by detection by the paper detection sensor 60, the speed of the paper 10 is reduced from a predetermined paper feed speed to zero.

[0006]

According to the above-mentioned prior art, if the paper feed speed (fixed) is set faster in order to feed the paper 10 faster, that is, if the motor is rotated at a higher speed, the stoppage of the motor 10 is stopped. The deceleration distance D required for this becomes longer. As a means for securing a sufficiently long distance D, the distance d
A method in which the paper detection sensor 60 is moved as close to the paper feed roller 19 as possible while keeping
A possible method is to increase the distance d2 between the paper feed roller 19 and the paper feed roller 19 and thereby increase the distance d1.

However, in the case of the former method, if the paper detection sensor 60 is provided at a position very close to the paper feed roller 19, interference with the paper feed roller 19 causes an obstacle in the detection of the paper 10. Therefore, this method has a limit in increasing the distance D. For this reason, there is a limit in increasing the paper feeding speed.

On the other hand, in the latter method, the paper detection sensor 60 can be separated from the print head 16 while eliminating the interference of the paper feed roller 19. However, since the distance d2 between the print head 16 or the platen 20 and the paper feed roller 19 becomes long, the type of the paper 10 is limited. That is, the sheet 10 whose size in the sheet feed direction is smaller than the distance d2 is the platen 20 and the sheet feed roller 1
9, and cannot be used as paper. Further, when the distance d2 is long, the size of the printer in the paper feeding direction is increased.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a printer in which the paper feed speed is variable according to the value of the top margin of the paper. Another object of the present invention is to provide a printer in which the paper feed speed is increased as a whole.

Another object of the present invention is to provide a printer which can handle small-sized paper and is suitable for miniaturization. A further object of the present invention is to provide a printer capable of realizing a high-quality paper feeding function at a low cost with a reduced number of components.

[0011]

FIG. 1 is a block diagram showing the principle of the present invention, and shows a printer according to the present invention. The printer includes an input device 8 for inputting a value of a top margin of a sheet, a motor 7 for feeding the sheet, a sensor 6 for detecting a leading edge of the sheet, and a sheet fed by controlling the motor 7. And a paper feed processing unit 2. The paper feed processing unit 2 determines the paper feed speed according to the value of the top margin of the paper input from the input device 8, accelerates the motor 7 until the speed is reached, and detects the leading edge of the paper by the sensor 6. The motor 7 is decelerated at the specified timing.

[0012]

The deceleration distance D is defined as the time between the start of the deceleration of the motor 7 rotating to feed the paper and the stop thereof.
The distance to send the paper. That is, the leading end of the sheet is detected by the sensor 6, and the motor 7 starts decelerating by this. When the motor 7 stops, the first printing line of the sheet must be located below the print head (16).

Accordingly, the actual deceleration distance D is the sum of the distance d1 between the sensor 6 and the print head (16) and the value d3 of the top margin of the paper. The value d3 of the top margin of the sheet is input by the operator from the input device 8, and indicates the distance from the top edge of the sheet (the leading end in the feeding direction) to the top position of the first line of the print.

From the above, the actual deceleration distance D is equal to the distance d1
Is determined by the device and is invariable, and thus is determined depending on the value d3. For example, if the value d3 is large, the value increases in accordance with the value.

Therefore, in the present invention, the paper feed speed is determined according to the value d3 of the top margin of the paper. That is, when the value d3 is large, the paper feeding speed is increased, and when it is small, the paper feeding speed is decreased.

Thus, when the actual deceleration distance D is large, that is, when the value d3 is large, even if the paper feeding speed is increased, the value d3 is large even if the paper feeding speed is increased. Can be reliably stopped at the position where it is set. On the other hand, when the actual deceleration distance D is small, that is, the value d3
Is small, the paper can be stopped at the position where the first line of the print comes under the print head by reducing the paper feed speed, even if the value d3 is small.

As described above, by making the paper feed speed variable and determining the value by the value of the upper end margin d3 of the paper, the paper feed speed can be optimized for each paper, so that the overall speed can be increased, and The sheet can be reliably stopped at a desired position.

[0018]

FIG. 2 to FIG. 4 are structural views of an embodiment, showing a printer according to the present invention. Hereinafter, an embodiment will be described with reference to FIGS. FIG. 3 is a diagram corresponding to FIG. In this embodiment, the sensor 6 is a mark reading sensor 6A, and the motor 7 is an LF motor 7A.
The input device 8 is a console 8A.

In FIG. 2, a CPU (central processing unit) 1
1 constitutes the processing device 1 together with the memory 12. Memory 1
2 has a control program 21 and a data storage RAM (storage unit) 22. A routine (paper feed control routine) for executing the paper feed process in the control program 21 constitutes the paper feed processing unit 2 together with the CPU 11.

The paper feed processor 2 has a speed setting table 3, a slewing curve table 4, and a speed calculator 5. More specifically, the paper feed control routine has a speed calculator 5 as a part thereof, and has a speed setting table 3 and a slewing curve table 4 in the data storage RAM 22. Note that these two tables are collectively referred to as an acceleration pulse table.

The speed setting table 3 stores the paper feed speed v determined according to the value d3 of the top margin of the paper.
The paper feed speed v is predetermined and is an appropriate value empirically obtained according to the value d3. The slewing curve table 4 stores a control signal T of the LF motor 7A according to the sheet feeding speed. This control signal T can be predetermined by calculation based on the configuration of the LF motor 7A. The speed calculator 5 calculates the paper feed speed v according to the value d3. An equation for this calculation can be predetermined based on the configuration of the LF motor 7A and the like.

The paper feed processor 2 includes a speed setting table 3
, Or the calculation by the speed calculation unit 5, the paper feed speed v is obtained using the value d3 of the upper end margin of the paper input from the console 8A. Therefore, either one of the speed setting table 3 and the speed calculating unit 5 may be provided alternatively. Using the obtained speed v, the sheet feed processing unit 2
Reads the control signal T of the LF motor 7A with reference to the slewing curve table 5, and controls the LF motor 7A with the control signal T. That is, it accelerates, performs a constant speed operation, and decelerates.

The LF motor 7A is a motor 7 for mainly feeding and feeding a sheet, and is a pulse motor for accurately controlling the position of the sheet. At the time of sheet feeding, the sheet feeding processing unit 2 or the CPU 11 sends an acceleration pulse P formed based on the obtained control signal T to the line feed control unit 13, and controls the LF motor 7A via this. The line feed control unit 13 controls the LF motor 7A based on the acceleration pulse P.
Is formed.

At the time of line feed (at the time of printing), the paper feed processing unit 2 or the CPU 11 controls the LF motor 7A via the line feed control unit 13 based on a predetermined line feed signal, and performs a line feed synchronized with the printing process.

An instruction input or the like for a paper feeding process prior to printing is input from the console 8A, and character data to be printed is transmitted from the main unit 9 of the printer. The console 8A is an input device 8 having a keyboard and a display device. The operator inputs predetermined instructions from the keyboard according to the screen displayed on the display device of the console 8A. For example, a margin value d3 at the upper end (and lower end, left end, right end) of the sheet, the number of copies, an instruction to start printing, and the like are input. For example, in response to an input to start printing, the sheet feed processing unit 2
Is activated, and a sheet feeding process is performed.

The main unit 9 is, for example, a host computer or the like, and sends data to be printed to a printer. This data is stored in the data storage RAM 22 via the CPU 11, read out at the time of printing, and sent to the print control unit 14.

A routine (print control routine) for executing a printing process in the control program 21 constitutes a print processing unit (not shown) together with the CPU 11. The print processing unit
When the paper feed process is completed, the printer is started by the paper feed processing unit 2, controls the CR motor 15 and the print head 16 via the print control unit 14 to execute the print process, and
A predetermined line feed signal is formed and sent to the sheet feed processing unit 2.

The print head 16 is mounted on a print head carriage (17) and is of a dot matrix type impact type. The configuration of the head pins is, for example, a configuration in which 24 pins (24 dots) are arranged in the paper feed direction (vertical).

The CR motor 15 is a motor that mainly drives the print head carriage. The print head carriage is driven in a direction perpendicular to the sheet feeding direction, and includes a mark reading sensor 6A.

The mark reading sensor 6A is a sensor 6 for optically detecting the leading end (upper end) of the fed sheet, and optically detects a predetermined mark (for example, a bar code) printed on the sheet. It has a reading function. That is, the mark reading sensor 6A is used as a sensor for detecting the sheet (leading edge) during the sheet feeding process, and is used as a mark reading sensor during the mark reading process.

When the mark reading sensor 6A detects the leading edge of the sheet during the sheet feeding process, the sheet feeding processor 2
Reads the control signal T using the previously obtained control signal T or again with reference to the slewing curve table 4, and based on this reads out the LF motor 7A to decelerate and stop. As a result, the paper is printed below the print head 16 in the first position.
It stops at the position where the line exists, and ends the sheet feeding process.

When the mark reading sensor 6A reads a bar code printed in advance on a sheet during the mark reading process, the print processing unit reads the bar code out of the data from the main unit 9 stored in the data storage RAM 22. Read and print the data indicated by the code.

In FIG. 3, the paper 10 is fed at a predetermined paper feed speed in the direction of the arrow. First, when printing start is input from the console 8A, the paper feed processing unit 2 performs paper feeding (advance feed) prior to printing. As described above, the paper feed speed v is obtained using the value d3 of the upper margin of the paper 10 input from the console 8A. The LF motor 7A, which is a driving source of the paper feed, is accelerated by the paper feed processing unit 2 and operated at a constant speed so that the paper feed speed v becomes the obtained value, and a pickup roller (not shown)
Then, the paper feed roller 19 is driven to convey the paper 10.

The paper 10 is picked up from a hopper (not shown) by a pickup roller, and is fed on a guide 18 to a paper feed roller 19. Further, the paper 10 is taken in from a paper inlet of a pair of upper and lower paper feed rollers 19, and is sent via a guide 18 between the platen 20 and the print head 16, that is, below the print head 16.

A mark reading sensor 6 A is provided on the print head carriage 17 together with the print head 16. In this embodiment, since the distance d1 between the print head 16 and the mark reading sensor 6A is extremely small, the print head 16 and the mark reading sensor 6A are shown in FIG. The mark reading sensor 6A is actually provided closer to the paper feed roller 19 than (the front end of) the print head 16 at a minute interval in the paper feed direction.

When the paper 10 reaches the vicinity of the print head 16, its leading end is detected by the mark reading sensor 6A. In response to this detection, the paper feed processing unit 2 controls the LF motor 7A to start reducing the paper feed speed v,
When the first line of printing reaches immediately below the print head 16, the LF motor 7A is stopped to stop the paper 10 at that position. This is the end of the sheet feeding (advance) processing.

Next, printing processing by the print head 16 is performed. That is, the print processing unit reads out the data to be printed from the data storage RAM 22, and performs printing by the print head 16 via the print control unit 14 based on the data. At this time, the print head carriage 17 is moved in a direction orthogonal to the paper feed direction by the CR motor 15 in accordance with the print timing, and the paper 10 is fed in the paper feed direction by the LF motor 7A to cause a line feed.

When the printing process is completed, the sheet feed processing section 2 performs sheet discharge again. The paper discharge speed is, for example, a predetermined relatively high constant speed. Therefore, the paper feed processing unit 2 refers to the slewing curve table 4 using the determined speed, and
The control signal of A is read out and the LF motor 7A is
Drive. Thus, the paper discharge roller 24 is driven, and the paper 10 is discharged to the stacker 25 via the guide 23.

FIG. 4 is a perspective view showing the actual structure near the print head carriage 17. In FIG. 4, the print head carriage 17 is formed of a rectangular portion provided close to the paper feed roller 19 on the paper feed direction (arrow direction) side. The lower part of the print head carriage 17 is
0 is sent in the direction of the arrow. Accordingly, the paper feed roller 19 in the drawing is the upper one of the pair of upper and lower rollers. A paper discharge roller 24 is provided adjacent to the print head carriage 17 in the direction of the arrow.

A print head 16 and a mark reading sensor 6A are provided on the print head carriage 17. Below the print head 16, the print head carriage 17 is provided with an opening. As a result, the head pin is
0 surface is impacted.

A mark reading sensor 6A is provided on the left side of the print head 16 in the drawing. The mark reading sensor 6A
A mark, for example, a bar code, printed on the surface of the paper 10 passing below the print head carrier 17 is read. That is, the bar code of the paper 10 is
The bar code is read by scanning the print head carriage 17 in the left-right direction in the figure while positioning it at the bottom.

FIGS. 5 and 6 show the sheet feeding in this embodiment in detail. In FIG. 5, the paper feed direction is from right to left in the figure (arrow direction). As described above, the print head 16 has a configuration in which 24 pins (dots) are arranged in the paper feed direction. The reading position of the mark reading sensor 6A is aligned with the center of the print head 16, that is, between the twelfth pin and the thirteenth pin from the right (front side of the paper feed).

As the position of the sheet 10, the sheet 1 shown in FIG.
Consider 0A to 10D. Although the upper end (the leading end in the paper feed direction) of the sheet 10A has reached below the print head 16, the upper end has not yet been detected by the mark reading sensor 6A. The sheet 10B is in a state where the upper end is detected by the mark reading sensor 6A.
The paper 10C is in a stopped state at the position where the upper end thereof coincides with the front end (the 24th pin from the right) of the print head 16, and shows a case where the value of the upper end margin d3 = 0. Paper 1
0D is a distance d3 whose upper end is from the tip of the print head 16.
This is a case where only the extra data has been sent and stopped, and the value d3 has a certain value.

In the paper feeding process, the paper 10 is accelerated at a certain rate (acceleration) to a constant speed v (determined by the value d3), and then is fed at a constant speed. The sheet is fed at a constant speed in the state of the sheet 10A, and is detected by the mark reading sensor 6A when the state of the sheet 10B is reached. With this as a trigger, the vehicle is then decelerated by the acceleration during acceleration (the sign is reversed), and stops at the position of the sheet 10C or the sheet 10D according to the value d3.

In the case of the sheet 10C, the deceleration distance D is d
Since 3 = 0, it is equal to the distance d1. The distance d1 is the distance between the mark reading sensor 6A and the print head 16, and more specifically, the reading position of the mark reading sensor 6A is set at the tip of the print head 16 (the left end of the 24th pin from the right in the figure). Is the distance between This is equal to 12 head pins of the print head 16 as described above. The leading end of the print head 16 is, as shown, a sheet 10C.
At the position that matches the top edge of

In the case of the sheet 10D, the deceleration distance D is d3
+ D1. That is, the length is increased by the value of the upper end margin d3. As shown in the figure, the leading end of the print head 16
Is located at a distance d3 from the upper end of.

After that, the sheets 10C and 10D are printed on their surfaces in accordance with the print data. In this printing, one character is represented by, for example, 24 dots vertically and 24 dots horizontally. That is, in the papers 10C and 10D, 24 dots of the first line of the print are present under the print head 16.

As described above, when the value d3 = 0, the paper 10C
Is stopped after being sent by 12 pins after the detection of the leading end. Therefore, even if the value d3 is the minimum value “0”, the paper 10C is allowed to run for 12 pins after the leading edge is detected.

By utilizing this, when the speed of the sheet 10 is reduced at a certain negative acceleration, the distance of the sheet 10 is D = d1
If the speed v (of the constant speed operation) of the paper 10 is selected so as to stop at (d3 = 0), the paper 10 can be stopped at the position where the paper 10 has traveled the distance d1 after the detection of the leading end. Further, after selecting the speed of the paper 10 as described above,
By decelerating at a rate equal to the acceleration when 0 is accelerated, the paper 10 can be surely stopped at the position of the distance d1.

On the other hand, if d3> 0, the deceleration distance D is d3
It becomes longer by the amount of Therefore, if acceleration and deceleration are performed at the same acceleration as when d3 = 0, the time for acceleration and deceleration can be lengthened by d3, and the paper 10 can be fed at a higher speed. That is, the feed speed v of the sheet 10 is determined depending on the value d3 of the upper margin.

Therefore, according to the present invention, the paper feed speed v
Can be optimized according to each sheet 10, the sheet feeding can be speeded up as a whole, and a high throughput can be achieved. That is, when the value of the upper margin is d3 = 0, the value is not so large. For this reason, when d3 = 0, it can be said that even if the paper feed speed is slightly lower than in the past, the effect is not so large.
On the other hand, when the value d3 is large to some extent, the paper 10 can be fed at an extremely high speed, which has not been possible in the past. This is because d3 =
Since we had to set the speed assuming the case of 0,
This is because the speed could not be increased even if there was sufficient margin.
As described above, according to the present invention, the paper feed speed v is set to the value d3.
, The speed can be increased as a whole.

Further, according to the present invention, the distance d1 between the mark reading sensor 6A and the print head 16 can be reduced by utilizing the fact that the paper feed speed v is variable. That is, although the paper feed speed v is originally changed depending on the value d3, when d3 = 0, that is, when the distance D = d1
If the speed v at the time of is reduced to some extent, the distance d
1 can be reduced.

Therefore, in this embodiment, as can be seen from a comparison between FIG. 3 and FIG. 8, the distance d1 is extremely small (for 12 pins). Thereby, the size of the printer can be reduced in the paper feeding direction. Further, since the distance between the paper feed roller 19 and the platen 20 can be reduced, the paper 10 having a short size in the paper feed direction can be handled.

Further, by utilizing the fact that the distance d1 can be reduced, both the reading of the mark and the detection of the leading edge of the sheet 10 can be performed by one sensor 6A.
That is, a sensor for reading a mark must be mounted on the print head carriage 17 and scan the paper surface perpendicularly to the paper feeding direction, since the mark is usually made of a bar code. On the other hand, if the distance d1 is large, a sensor for detecting a sheet cannot be mounted on the print head carriage 17.

In this embodiment, the distance d1 is reduced, and a sensor for detecting a sheet is mounted on the print head carriage 17. Thus, one sensor 6A can perform both mark reading and sheet detection. Therefore, at a low cost, it is possible to realize not only the sheet detection but also the high function of reading the mark.

In FIG. 6, the paper feed processing unit 2 is started by input of a print processing start instruction from the console 8A, takes in the value d3 of the upper margin input from the console 8A, and uses this value d3 to execute a speed setting table. 3, the acceleration pulse number P stored according to the value d3 is read. By accelerating by the number of acceleration pulses P, the paper feed and speed v are determined.

The speed setting table 3 stores the number of acceleration pulses P according to the value d3 (mm). The value d3 is, for example, 0.
It can be set in units of 1 mm, the lower limit is 0 mm, the upper limit is, for example, a few cm, and the number of acceleration pulses P
Is stored.

If the paper 10 is fed by 1/360 inch per pulse, the number of acceleration pulses P0 when d3 = 0 is 27 in FIG. Speed v
Is determined according to the characteristics of the printer, is obtained empirically,
This is a value that can be decelerated to “0” at the distance D. The speed v defines the speed of the sheet 10 when the LF motor 7A is accelerated and is operating at a constant speed.
The range is from 0pps (pulse / second, the number of pulses to be transmitted per second) to 3600pps.

Next, the paper feed processing unit 2 sequentially refers to the slewing table 4 by the number of acceleration pulses P read from the speed setting table 3 and reads the stored control signal T in accordance with the number.

The slewing curve table 4 stores a sheet feed control signal T according to a speed v (pps) determined by the number of acceleration pulses P. The control signal T is a pulse train for accelerating (or decelerating to "0") the LF motor 7A, which is a pulse motor, to the speed v.

Assuming that the lower limit of the speed v is 500 pps, the time interval (period) at which pulses are transmitted at this time is 2.0 msec. Assuming that the upper limit of the speed v is 3600 pps, the time interval of the pulse transmission at this time is 0.277 msec. Therefore,
When the speed v is accelerated from 500 pps to 3600 pps, the control signal T is transmitted at time intervals of, for example, 2.0, 1.5, 1.
The pulse train gradually decreases to 2, ... 0.277 (msec).

The actual slewing curve table 4 is
As shown in FIG. 6, the transmission interval (msec) of the pulse applied to the LF motor 7A for feeding the paper is stored according to the value of the speed v (pps). Therefore, the actual control signal T is a data string indicating a pulse transmission interval.

Assuming that the speed v is 500 pps, the paper feed processing unit 2 reads out the transmission interval 2.0 (msec) from the slewing curve table 4. Further, assuming that the speed v is 3600 pps, a data string having a transmission interval of 2.0, 1.5, 1.2,... 0.277 (msec) is read. As described above, the read data sequence defines the transmission interval, and can be considered as a pulse sequence for accelerating to the speed v.

As described above, the speed setting table 3
If the speed calculation unit 5 is provided instead of the
Sends the value d3 of the upper end margin inputted from the console 8A to the speed calculation unit 5 and requests the speed calculation unit 5 to calculate the speed v (the number of acceleration pulses P). The speed calculator 5 calculates the speed v according to a predetermined calculation formula. This formula is empirically determined and depends on the characteristics of the printer. The paper feed processing unit 2
The control signal T is obtained by referring to the slewing curve table 4 using the speed v obtained by the speed calculator 5.

Next, the paper feed processing unit 2 forms an acceleration (or deceleration) pulse using the control signal T, and the line feed control unit 1
3 and is applied to and driven by the LF motor 7A. The actual driving pulse of the LF motor 7A is formed by the line feed control unit 13 based on the acceleration pulse P.

For example, when the value of the upper end margin d3 = 0, the speed v = 1900 pps, the number of acceleration pulses P = 27, and the control signal T =
Since the acceleration pulse is 2.0 (msec), a second pulse is transmitted 2.0 msec after the transmission of the first pulse, and a third pulse is transmitted 1.5 msec after the transmission of the second pulse.
Thereafter, similarly, a total of 27 pulses are transmitted and acceleration is performed.
As a result, as shown by the solid line in FIG. 6, the LF motor 7A accelerates the speed v (1900) after accelerating 27 pulses from the speed “0”.
pps), and then operate at a constant speed.

When the sheet 10 reaches below the mark reading sensor 6A by the constant speed operation, the mark reading sensor 6A detects the leading end of the sheet 10 and notifies the sheet feed processing section 2 of this. In response to this notification, the paper feed processing unit 2 decelerates according to the control signal T. That is, the transmission of the subsequent pulses is stopped. As a result, the LF motor 7A stops, and the paper 1
Feeding of 0 also stops.

At this time, since the accelerations during acceleration and deceleration are equal, the inclination θ is equal. Further, the amount of the sheet 10 fed during the deceleration period (from the detection of the leading edge to the stop of the sheet 10) is equal to d1. Since the paper feed speed v (1900 pps) is set so as to advance by the distance d1 and stop the paper 10, the leading end of the paper 10 coincides with the leading end of the print head 16 as shown as the paper 10C in FIG. Stop at the position.

Next, when the value d3 of the upper margin is sufficiently large, the speed v = 3600 pps, the control signal T = 2.0, 1.5, 1.2,
.. 0.277 (msec), the acceleration pulse P is transmitted the second pulse 2.0 msec after the transmission of the first pulse, and thereafter the pulse transmission interval is 1.5 msec, 1.2 msec.
It is shortened to 7 msec in order, and transmitted at 0.277 msec thereafter.
As a result, the LF motor 7A is accelerated from the speed "0" as shown by the dotted line in FIG. 6, reaches the speed v = 3600 pps, and thereafter operates at a constant speed.

When the leading end of the sheet 10 is detected by the mark reading sensor 6A, the sheet feed processing unit 2
Set the sending interval of acceleration pulse P to 0.27
The last pulse is transmitted 2.0 msec after the transmission of the immediately preceding pulse (the second latest pulse), and the transmission of subsequent pulses is stopped. That is, the control signal T is used in the reverse order of the acceleration.

At this time, since the same slewing curve table 4 as when d3 = 0 is used, the inclination of the acceleration is θ. Further, the amount by which the paper 10 is fed during the deceleration period is equal to d1 + d3.

The acceleration pulse P at the time of acceleration is, for example,
Control signals T = 2.0, 1.5, 1.2,... 0.277 (msec) are used in this order, and the acceleration pulse P at the time of deceleration is the same as the control signal T
Are used in reverse order. Therefore, the control signal T at the time of deceleration may be obtained at the time of acceleration. In this case, the paper feed processing unit 2 temporarily stores the control signal T in the register of the CPU 11. Also, at the time of deceleration, the control signal T may be obtained again in the same manner as at the time of acceleration.

FIG. 7 shows the flow of the sheet feeding process. When receiving an instruction to start printing, the paper feed processing unit 2 reads the value of the upper end margin d3 input from the console 8A, for example, from the data storage RAM 22 (S1).

Next, the paper feed processing unit 2 refers to the acceleration pulse table using the value d3, determines the number of acceleration pulses P corresponding to the value d3, and obtains a control signal T corresponding to the number of acceleration pulses P ( S2).

Next, the paper feed processing section 2 forms an acceleration pulse based on the control signal T, applies the acceleration pulse to the LF motor 7A via the line feed control section 13, and feeds the paper 10 (first feed).
Is started (S3). The LF motor 7A is accelerated according to the acceleration pulse, and thereafter is operated at a constant speed v.

The paper feed processor 2 checks whether or not there is a notification of the detection of the paper 10 from the mark reading sensor 6A (S10).
4) Repeat S4 periodically until notified. When the sheet detection notification is received, the sheet feed processing unit 2 controls the control signal T
LF motor 7A according to the acceleration pulse formed by using
Is decelerated (S5). The LF motor 7A stops after sending the sheet 10 for a predetermined distance D.

[0077]

As described above, according to the present invention,
By determining the paper feed speed according to the value of the top margin of the paper in the printer, the paper feed speed can be set to an appropriate value for each paper, so the overall paper feed speed is increased and the throughput is improved. It is also possible to handle small-sized paper, and to reduce the size of the printer. Further, since the paper feeding speed is variable, a sensor for detecting the paper can be mounted on the print head carriage, so that the paper detection and the mark reading can be performed by one sensor, and the cost is low. A high-performance printer can be realized.

[Brief description of the drawings]

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

FIG. 2 is a configuration diagram of an embodiment.

FIG. 3 is a configuration diagram of an embodiment.

FIG. 4 is a configuration diagram of an embodiment.

FIG. 5 is an explanatory view of an embodiment.

FIG. 6 is an explanatory diagram of an embodiment.

FIG. 7 is a flowchart of a sheet feeding process.

FIG. 8 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

 Reference Signs List 1 processing device (CPU / memory) 2 paper feed processing unit 3 speed setting table 4 slewing curve table 5 speed calculation unit 6 sensor 7 motor 8 input device 9 main unit 10 paper 11 CPU 12 memory 13 line feed control unit 14 print control unit 15 CR motor 16 print head 17 print head carriage 18 guide 19 paper feed roller 20 platen 21 control program 22 data storage RAM 23 guide 24 paper discharge roller 25 stacker

Claims (4)

(57) [Claims] An input device for inputting a value of a top margin of a sheet; a motor for feeding a sheet; a sensor for detecting a leading end of the fed sheet; (7) a sheet feed processing unit (2) for feeding a sheet by controlling the sheet feed processing unit (2), wherein the sheet feed processing unit (2) controls the sheet feed according to the value of the upper end margin of the sheet input from the input device (8). A printer that determines a speed, accelerates the motor (7) until the speed reaches the determined speed, and decelerates the motor (7) when the leading edge of the sheet is detected by the sensor (6). . 2. The paper feed processing section (2) includes a speed setting table (3) for storing a predetermined paper feed speed according to a value of a top margin of the paper, and receives an input from the input device (8). 2. The printer according to claim 1, wherein the sheet feed speed is determined by referring to the speed setting table using the value of the upper edge margin of the sheet. 3. 3. The paper feed processing unit (2) further comprises a speed calculation unit (5) for calculating a paper feed speed according to a value of a top margin of the paper, and the speed calculation unit (5) performs the input by the speed calculation unit (5). 2. The printer according to claim 1, wherein the paper feed speed is obtained by using a value of a top margin of the paper input from the device (8). 4. The print head (1) includes a sensor (6).
The print head carriage (17) having the function (6) has a function of reading a predetermined mark pre-printed on a sheet, and is used for detecting the leading edge of the sheet when feeding the sheet. The printer according to claim 1, wherein