JP2001328301A - Recorder and its controlling method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a recorder and its controlling method in which paper thickness detection can be executed without lowering the throughput and without increasing the cost. SOLUTION: The recorder for detecting the thickness of a cut sheet being fed from a sheet feeder at a specified timing, adjusting the platen gap depending on the detected thickness of the cut sheet and then executing recording operation on the cut sheet comprises means for detecting a state where no print data is present, and means (S4-S9) for detecting the thickness of a first sheet being fed from the sheet feeder following to continuation of a state where no print data is present for a predetermined time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a recording apparatus capable of executing recording and writing on cut sheets such as cut sheets and copy sheets, and a control method therefor.

[0002]

2. Description of the Related Art In general, a sheet thickness detecting means for detecting a sheet thickness of a cut sheet fed from a sheet feeding device is provided, and a platen gap is set according to the sheet thickness of the cut sheet detected by the sheet thickness detecting means. There is known a recording apparatus which automatically adjusts and performs a recording operation on the cut sheet. In this type of conventional paper thickness detecting means, when the cut sheet is not interposed, first, the print head is brought into contact with the platen, the position of the platen surface is measured, and then the cut head is interposed and the print head is interposed. Generally, the position of the cut sheet surface is measured by contacting the upper cut sheet, and the sheet thickness of the cut sheet is measured from the difference between the positions.

Conventionally, this paper thickness detection is performed every time a cut sheet is supplied to a recording unit, or the sheet thickness is detected by a paper remaining amount detector provided in the paper feeding device. Has been executed, and paper thickness detection has been executed only when this is detected.

[0004]

However, when detecting the paper thickness every time, there is a problem that the detection time is long and the throughput is reduced.

Further, when it is detected that the exchange of cut sheets has been performed, and only when this is detected, when the paper thickness detection is performed, a paper remaining amount detector must be provided in the paper feeding device. However, there is a problem that the cost increases accordingly.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a recording apparatus and a recording apparatus capable of executing paper thickness detection without lowering the throughput and without increasing the cost. It is to provide a control method.

[0007]

According to a first aspect of the present invention, a sheet thickness of a cut sheet fed from a sheet feeding device is detected at a predetermined timing, and the thickness of the cut sheet is detected according to the detected sheet thickness. In a printing apparatus that adjusts a platen gap and performs a printing operation on the cut sheet, a means for detecting a print data absence state, and when the print data absence state continues for a predetermined time, a sheet is then fed from a sheet feeding apparatus. Means for detecting the paper thickness of the first cut sheet.

According to a second aspect of the present invention, in the first aspect, when the cut sheets fed from the sheet feeding device are from different bins, it is determined whether or not the print data absence state has continued for a predetermined time. Regardless of the above, the paper thickness is detected.

The invention described in claim 3 is the first or second invention.
The paper thickness described above is characterized in that the paper thickness is detected when the first paper supply immediately after the paper-out error occurs, regardless of whether or not the print-data-out state has continued for a predetermined time.

According to a fourth aspect of the present invention, a sheet thickness of a cut sheet fed from a sheet feeder is detected at a predetermined timing, and a platen gap is adjusted according to the detected sheet thickness of the cut sheet. In the control method of executing a recording operation on a cut sheet, a state where there is no print data is detected,
When this print data absence state continues for a predetermined time, the sheet thickness of the first cut sheet fed from the sheet feeding device is detected thereafter.

According to a fifth aspect of the present invention, in the fourth aspect, when the cut sheets fed from the sheet feeding device are from different bins, it is determined whether or not the print data absence state has continued for a predetermined time. Regardless of the above, the paper thickness is detected.

The invention according to claim 6 is the invention according to claim 4 or 5.
The paper thickness described above is characterized in that the paper thickness is detected when the first paper supply immediately after the paper-out error occurs, regardless of whether or not the print-data-out state has continued for a predetermined time.

In the present invention, the sheet thickness is not always detected for the cut sheet fed from the sheet feeding device. If the print data absence state does not continue for the predetermined time, the cut sheet is not detected and the cut sheet is immediately conveyed to the cueing position and printing is performed.

That is, when the cut sheet does not continue for a predetermined time, it is estimated that the cut sheet stored in the sheet feeding device has not been replaced.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing a dot impact printer to which an embodiment of the recording apparatus according to the present invention is applied. The printer 10 is a printer that prints an image including characters by hitting a number of recording wires on a sheet via an ink ribbon (both not shown) and recording dots.

The printer 10 includes a printer main body 11 as a recording apparatus main body, a sheet supply guide 43 which is provided on the front side of the printer main body 11 and is configured to allow a cut sheet K to be manually inserted thereinto. And a sheet feeding device CSF installed at the rear side for automatically feeding the cut sheet K to the recording unit.

FIG. 2 shows the printer main body 11 from which the paper feeding device CSF has been removed. A push tractor unit (continuous sheet conveyance device) 12 that supplies a continuous sheet to a recording unit is disposed substantially below the sheet feeding device CSF.

The sheets include the cut sheet K cut to a predetermined length and a continuous sheet formed by connecting a plurality of sheets. The cut sheet K is, for example, a cut film such as a cut sheet, a copy sheet, or an OHP (overhead projector) sheet, and the continuous sheet is a continuous sheet.

FIG. 3 shows a sheet conveying mechanism of the printer main body 11. The sheet transport mechanism 30 includes a paper feed roller 13 connected to the push tractor unit 12 described above.
, A platen 20 and a transport roller unit 21.

As shown in FIG. 4, a carriage 31 is provided above the platen 20, and a ribbon cartridge 35 and a print head 36 are mounted on the carriage 31. The carriage 31 is supported by a carriage guide shaft 32 and moves by scanning above the platen 20 in the axial direction of the platen 20.

The carriage guide shaft 32 is rotatably supported between the side frames 33 and 34. As shown in FIG. 5, the carriage guide shaft 32 has an eccentric shaft 32A having an eccentric center axis at an end thereof, and a gear 37 is fixed to the eccentric shaft 32A. This eccentric shaft 32
The amount of eccentricity of A with respect to the carriage guide shaft 32 is, for example, about L = 1 mm. 40 is a lead wire.

As shown in FIG. 6, a gear 38 meshes with the gear 37, and an output gear 39A of a stepping motor 39 meshes with the gear 38. This output gear 39
A slit plate 41 is mounted coaxially with A, and a rotary encoder 42 is mounted facing the slit plate 41, and the rotation angle of the slit plate 41 is detected by the rotary encoder 42.

When the stepping motor 39 is driven, the output gear 39A, the gear 38 and the gear 37
The eccentric shaft 32A rotates, and the carriage guide shaft 32 rotates integrally therewith. Then, this carriage guide shaft 3
2 moves vertically in the vertical direction by the amount of eccentricity (2 mm if L = 1 mm).
The carriage 31 supported by the print head 2 and the print head 36 integrated with the carriage 31 move toward and away from the platen 20.

Next, the operation of the recording apparatus will be described.

When a cut sheet K such as a cut sheet or a copy sheet is manually supplied, first, the cut sheet K is manually supplied from the front side of the printer body 11 in FIG. The rotation of the platen 20 and the paper feed roller 13 causes the printer body 11 to be transported from the front to the rear. The rotation of the transport roller unit 21, the platen 20, and the paper feed roller 13 causes the print head 36 to be reversed and transported forward from the rear of the printer main body 11 to the front, facing the platen 20.
Is supplied to the recording unit including the print data, and printing is performed.

As shown in FIG. 2, a continuous sheet such as continuous paper is supplied from the rear side of the printer body 11 by a push tractor 12, and then conveyed in the same direction by a paper feed roller 13 and a conveyance roller unit 21. Then, the print data is supplied to the recording unit including the print head 36 facing the platen 20, and printing is performed.

Next, automatic paper feeding using the paper feeding device CSF will be described.

As shown in FIGS. 7 to 9, the paper feeder CSF picks up one hopper 91 holding a plurality of cut sheets K and one cut sheet K at the top of the hopper 91 one by one. The feed roller 92 that feeds and the cut sheet K that is double fed together with the uppermost cut sheet K
And a separation pad 93 for separating the two. The paper feed roller 92 has a D-shaped cross section having an arc portion 92a in contact with the cut sheet K and a linear portion 92b separated from the cut sheet K, and at least the surface is made of a high wear material such as rubber. ing.

One cut sheet K is fed to the paper feed roller 13 through the paper guide 98 during one rotation while the arc portion 92a of the paper feed roller 92 is in contact with the separation pad 93. The paper guide 98 is provided with a paper detector PE for detecting the leading end of the cut sheet K to be fed.

At the time of the automatic paper feeding, the paper feed rollers 1
The so-called skew removal of the cut sheet K is performed by the cooperation of the driving roller 13A and the driven roller 13B constituting the third sheet 3.

This skew removal is performed as shown in FIG.
The leading end of the cut sheet K is made to bite between the driving roller 13A and the driven roller 13B by a predetermined length L1.
2 with the drive roller 13A stopped in the direction shown in the figure,
That is, the rotation is performed in a direction opposite to the sheet feeding direction (reverse rotation).

After the skew removal is completed, as shown in FIG. 9, the drive roller 13A and the driven roller 13B are rotated in the normal direction to perform a cue operation of a fixed length L. Is sent to the area of the recording head 36 to perform recording. The cut sheet K recorded here is discharged via the transport roller unit 21 (FIG. 3).

In this embodiment, the thickness of the cut sheet K is detected at the following timing during the automatic paper feeding. Then, the distance between the print head 36 mounted on the carriage 31 and the platen 20 (hereinafter, referred to as a platen gap) is automatically adjusted according to the sheet thickness.

Next, the automatic adjustment of the platen gap will be described with reference to the flowchart shown in FIG.

First, as shown in FIG.
Are separated and conveyed (S1), and skew is removed (S2). Next, it is determined whether or not it is the first sheet feeding after the occurrence of the "paper out error" (S3). If it is not the first sheet feeding after the "paper out error", the process proceeds to step S4.

The "paper-out error" refers to FIG.
This is an error that is output when the paper detector PE should change to “paper present” after performing the paper feeding operation but does not change to “paper present”, and the cut sheet K is set in the paper feeder CSF. Occurs when a paper feed operation is performed in the absence state.

In step S4, on the assumption that the bin is the same as the previous paper feed (in this embodiment, two hoppers 91 are provided), the state of no print data is set for a predetermined time ( It is determined whether or not the operation has been continued (for example, 5 seconds).

The user can select which bin to print on the cut sheet K by operating a display panel operation button of the printer main body 11 or the like. The state of no print data is, for example, that all tasks are in an idle state. More specifically, the printer body 11
Is empty, meaning that all the motor and print head 36 jobs are stopped.

When the state of no print data is reached, a microcomputer (means for detecting the state of no print data)
, A print data absence state signal is output. Therefore, the output state of this signal is monitored, and if the print data absence state continues for a predetermined time, the sheet thickness of the cut sheet K is detected. The predetermined time is, for example, 5 seconds. This is because if the five seconds have elapsed, the cut sheet K of the sheet feeding device CSF may have been replaced.

The detection of the sheet thickness of the cut sheet K is performed as follows. First, as shown in FIG. 9, the cut sheet K is conveyed before the platen 20 (S5). In this state, the stepping motor 39 is driven to move the carriage 31 to the platen 20 as described above. Move in contact direction.

When the carriage 31 comes into contact with the platen 20, a load is applied to the stepping motor 39, and the stable position of the rotor and the stator of the stepping motor 39 deviates, so that the cycle of the output waveform of the rotary encoder 42 becomes longer. Since this period Ti is longer than the theoretical value Tro, (Ti-Tro)> 0. This (Ti-
Tro) is accumulated, and when the threshold value Tth is reached, the rotation of the stepping motor 39 is stopped, the number of pulses from the reference position at that time is stored, and the platen surface is measured (S6).

When the measurement of the platen surface is completed, the cut sheet K is then conveyed to a position directly above the platen (searching for a head) (S7). Then, in this state, the stepping motor 39 is driven to move the carriage 31 to the platen 2.
It is moved in the direction in contact with the upper cut sheet K. Carriage 31 is cut sheet K on platen 20
Contact with the stepping motor 39 as described above.
And the stable position of the rotor and the stator of the stepping motor 39 deviates, so that the cycle of the output waveform of the rotary encoder 42 becomes longer. Since this cycle Ti is longer than the theoretical value Tro, (Ti−Tro)> 0
Becomes When this (Ti-Tro) is accumulated and reaches the threshold value Tth, the rotation of the stepping motor 39 is stopped, the number of pulses from the reference position at that time is stored, and the sheet surface of the cut sheet K is stored. Is measured. Then, based on the respective positions of the sheet surface and the platen surface, the difference is obtained, and the paper thickness is calculated (S8).

After the measurement of the sheet thickness, the stepping motor 39 is driven to adjust the platen gap according to the sheet thickness (S9).

When the adjustment of the platen gap is completed, one-line printing is performed (S10), and it is determined whether or not a page break command has been output (S11). (S12), one-line printing is repeated.

When the page break command is output, the cut sheet K is discharged (S13), and it is determined whether or not there is print data (S14). If there is print data, the process proceeds to the first step S1. Go back and cut sheet K
Is carried out, and if there is no print data, the process ends.

In the present embodiment, the sheet thickness detection in S5 to S9 is not always performed on the fed cut sheet K.

In step S4, assuming that the bin is the same as that of the previous sheet feeding, the state where there is no print data is set for a predetermined time (for example, 5 minutes).
If the cut sheet K does not continue for 5 seconds, that is, if it does not continue for 5 seconds, the sheet thickness of the cut sheet K is not detected, and the cut sheet K is immediately conveyed to the cueing position (S15).
Perform line printing. That is, if you do not continue for 5 seconds,
It is presumed that the cut sheet K stored in the hopper 91 of the sheet feeding device CSF has not been replaced, and the sheet thickness of the cut sheet K is not detected. Perform line printing.

According to this, as compared with the case where the paper thickness detection is performed every time, the detection time can be shortened, and the throughput can be improved.

Further, by monitoring the state of no print data, the paper thickness can be detected at appropriate timing. The cost can be reduced by the amount of remaining paper detector.

In the present embodiment, when the cut sheet K fed from the sheet feeding device CSF is from a different bin, regardless of whether or not the print data absence state has continued for a predetermined time in S4, The paper thickness must be detected, and if the paper is the first paper feed immediately after the paper-out error has occurred (S
3) The paper thickness is always detected regardless of whether or not the print data absence state has continued for a predetermined time.

According to this, when the possibility that the sheet thickness of the cut sheet K changes is predicted beforehand, the sheet thickness detection is always performed.

As described above, the present invention has been described based on the above embodiment, but the present invention is not limited to this.

[0054]

According to the present invention, the paper thickness can be detected without lowering the throughput and without increasing the cost.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a printer main body of a dot impact printer to which an embodiment of a recording apparatus according to the present invention is applied.

FIG. 2 is a perspective view illustrating a printer main body from which a sheet feeding device CSF is removed.

FIG. 3 is a perspective view illustrating a sheet conveying mechanism of the printer body.

FIG. 4 is a perspective view showing a carriage.

FIG. 5 is a perspective view showing a platen gap adjusting mechanism.

FIG. 6 is a perspective view showing a carriage and a platen gap adjusting mechanism.

FIG. 7 is a diagram illustrating a procedure for conveying a cut sheet.

FIG. 8 is a diagram illustrating a cut sheet conveying procedure.

FIG. 9 is a diagram illustrating a procedure for conveying a cut sheet.

FIG. 10 is a flowchart illustrating an embodiment of the present invention.

[Explanation of symbols]

REFERENCE SIGNS LIST 10 printer (recording device) 11 printer main body 12 push tractor unit (continuous sheet transport device) 13 paper feed roller 20 platen 21 transport roller unit 31 carriage 36 print head 39 stepping motor CSF paper feeder K cut sheet

Claims (6)

[Claims] 1. A sheet thickness of a cut sheet fed from a sheet feeding device is detected at a predetermined timing, a platen gap is adjusted according to the detected sheet thickness of the cut sheet, and a recording operation is performed on the cut sheet. Means for detecting a state of no print data, and means for detecting the thickness of the first cut sheet fed from the sheet feeder when the state of no print data has continued for a predetermined time. A recording device comprising: 2. When the cut sheets fed from the sheet feeding device are from different bins, the sheet thickness is detected regardless of whether or not the print data absence state has continued for a predetermined time. 2. The recording apparatus according to claim 1, wherein: 3. The paper thickness is detected when the first paper supply immediately after the paper-out error occurs, regardless of whether the print-data-out state has continued for a predetermined time. 2. The recording device according to 2. 4. A sheet thickness of a cut sheet fed from a sheet feeding device is detected at a predetermined timing, a platen gap is adjusted according to the detected sheet thickness of the cut sheet, and a recording operation is performed on the cut sheet. In the control method to be executed, a print data absence state is detected, and when the print data absence state continues for a predetermined time, a sheet thickness of the first cut sheet fed from the sheet feeding device is detected thereafter. A method of controlling a recording apparatus. 5. When the cut sheets fed from the sheet feeding device are from different bins, the sheet thickness is detected regardless of whether or not the print data absence state has continued for a predetermined time. The control method for a recording apparatus according to claim 4, wherein 6. The paper thickness is detected when the first paper supply immediately after the paper-out error occurs, regardless of whether the print-data-out state has continued for a predetermined time. 6. The method for controlling a recording apparatus according to claim 5.