JPH07214833A - Printer - Google Patents

Abstract

PURPOSE:To save operators the trouble of resetting printing papers by providing a control part which determines whether or not the printing papers are loosened from the detecting result of a detecting member for printed test patterns. CONSTITUTION:Each of the ink ribbons 12 of different colors is provided with a different ink ribbon mark 21 near its end-part and the ink ribbon mark is detected by a detecting sensor 22 provided in a ribbon feeding path. The ink ribbon 12 is transferred by feed rollers 24 and 25 provided in the ribbon feeding path. Printing papers 11 are pressed against a platen 9 by the pressure rollers 19 and 20 rotatable with the rotation of the platen 9. The pressure roller 19 can be moved out of contact with the platen 9 and to the positions of broken line by a engage/disengage mechanism. A loosening mechanism is provided consisting of a mechanism for moving a printing head 2 into and out of contact with the platen 9 and a mechanism for moving the pressure roller 19 into and out of contact with the platen 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer for performing printing by pressing an ink ribbon, which is superposed and fed on a printing paper, against a platen by a printing head.

[0002]

2. Description of the Related Art Conventionally, there is a printer in which a printing sheet is pressed against a platen by a pressing member to be fed, and an ink ribbon superposed on the printing sheet is fed to a platen for printing. As such a printer, there is a multicolor thermal transfer recording apparatus that adopts a frame-sequential swing method.

The structure of a conventional multicolor thermal transfer recording apparatus will be described below with reference to the drawings. FIG. 12 is a schematic perspective view showing a conventional multicolor thermal transfer recording apparatus. In FIG.
The multicolor thermal transfer recording apparatus 1 is provided with a print head 2 having a line type heating resistor, and a platen 9 is provided so as to face the print head 2. Brackets 3 are attached to both sides of the print head 2, and one end of a spring 10 is attached to one end 3 a of the bracket 3. The other end of the spring 10 is attached to a frame (not shown), and the bracket 3 is attached with an arrow A.
The print head 2 is pressed against the platen 9 by being urged in the direction.

A cam 5 mounted on the shaft 4 is in contact with the other end 3b of the bracket 3. A gear 6 is also attached to the shaft 4, and the gear 6 meshes with a gear 8 attached to a rotation shaft (not shown) of the print head pulse motor 7 and is driven by the print head pulse motor 7. The cam 5 is adapted to rotate. In addition,
The print head 2 is pressed by the platen 9 by the biasing force of the spring 10 when the lift of the cam 5 is at the minimum position, and resists the biasing force of the spring 10 when the lift of the cam 5 is at the maximum position. The bracket 3 rotates about the fulcrum 23 in the arrow B direction, and the print head 2 also rotates in the arrow B direction and separates from the platen 9.

Between the print head 2 and the platen 9, a printing paper 11 running in the direction of arrow C from a paper roll 13 is provided.
And the ink ribbon 12 which is supplied together with the printing paper 11, travels in the direction of arrow D from the supply roll 14 and is wound up by the winding roll 15. The ink ribbon 12 has a width substantially the same as the width of the printing paper 11, and
The transfer inks for the three primary colors for printing 6, 6, magenta 17, and cyan 18 are applied in a size slightly larger than the set size of the normal printing area. In addition, the ink ribbon 12
Are provided with ink ribbon marks 21 of different types for each color of the ink ribbon 12 in the vicinity of the front end of each color, which are detected by a detection sensor 22 provided in the running path of the ink ribbon 12. The ink ribbon 12 is conveyed by feeder rollers 24 and 25 provided on the traveling path of the ink ribbon 12.

The printing paper 11 is pressed against the platen 9 by pressure rollers 19 and 20 which rotate with the rotation of the platen 9.

Next, the operation of printing on the printing paper 11 having the above-mentioned structure will be described. In FIG. 12, first, the operator sets the printing paper 11 and the ink ribbon 12 in the multicolor thermal transfer recording apparatus 1. When printing, the platen 9 is rotated in the direction of arrow E to rotate the printing paper 1
1 from the direction of arrow C to the direction of arrow G, and
The ink ribbon 12 is conveyed together with the printing paper 11 in the direction of arrow D by the rollers 24 and 25, and the printing head 2 prints yellow on the printing area of the printing paper 11. Thereafter, the print head pulse motor 7 is rotated to set the lift of the cam 5 to the maximum position, and the print head 2 is rotated in the direction of arrow B to separate the print head 2 from the platen 9.

Then, the platen 9 is rotated in the direction of arrow F, the printing paper 11 is fed backward from the direction of arrow H in the direction of arrow I to the initial position, and the ink ribbon 12 is fed by the feeder rollers 24 and 25. The paper is conveyed in the direction of arrow D, and magenta is positioned in the printing area of the printing paper 11. Then, the print head pulse motor 7 is rotated to set the lift of the cam 5 to the minimum position, and the print head 2 is rotated in the arrow J direction.
The print head 2 is pressed against the platen 9, and the print paper 11 and the ink ribbon 12 are conveyed together, and magenta printing is performed on the print area of the print paper 11.

Then, the printing paper 11 is fed back again and returned to the initial position. While the printing paper 11 and the ink ribbon 12 are conveyed together, cyan is printed in the printing area of the printing paper 11, and the printing is completed. The printing paper 11 is discharged outside the multicolor thermal transfer recording apparatus 1.

The print head 2 is positioned at a position away from the platen 9 during standby or when the ink ribbon 12 is running to set the print start position for each color.

[0011]

In the above-mentioned conventional multicolor thermal transfer recording apparatus, the operator operates the printing paper 11 in the apparatus.
If the printing paper 11 is not properly attached to the platen 9 as shown in FIG. 13, the printing head 11 may sag between the printing head 2 and the pressure roller 19 as shown in FIG. It was When the print sheet 11 is conveyed in this state, the slack of the print sheet 11 is gradually corrected as the print sheet 11 is conveyed in the direction of the arrow G by the rotation of the platen 9, but the slack of the print head 2 is reduced by the platen 9. When the platen 9 has a weak feeding force, the printing paper 11 sandwiched between the platen 9 and the print head 2 slips without being conveyed, and the printing area is fed with the printing paper. There is a problem that the length becomes shorter than usual in the sending direction.

The printing paper 11 includes a platen 9 and a printing head 2.
Since the printing paper 11 is fed from the direction of arrow C by the rotation of the platen 9 even while slipping between
As shown in FIG. 4, the print head 2 and the pressure roller 2
There is a problem in that a slack is generated between 0 and 0, and the slack also causes the print area to become shorter than usual in the print paper feeding direction, resulting in deterioration of print quality. .

Further, there is a problem that the operator has to reset the printing paper 11 in order to correct the slack generated in the printing paper 11.

[0014]

In order to solve the above-mentioned problems, the solution means provided in the present invention presses a printing sheet against a platen by a pressing member to feed the sheet, and the sheet is superposed on the sheet. In a printer that performs printing with a print head that presses the ink ribbon against the platen, a print head that prints a test pattern that is provided at a specified distance in the feeding direction of the ink ribbon on the print paper, and the printed test pattern is detected. A detection member and a control unit for determining whether or not there is slack in the printing paper based on the detection result of the detection member are provided, and the control unit causes the slack in the printing paper when a test pattern is detected by the detection member. If it is determined that the test pattern is not detected by the detection member, it is determined that the printing paper is not sagging.

In addition to the above-mentioned means, the pressing member and the print head are separated from the platen so that the print sheet is temporarily not pressed against the platen. A slack correction mechanism is provided to correct the slack by pressing the slack in the platen in the feeding direction.

[0016]

The test pattern is printed on the print sheet by the print head, and the print sheet is conveyed. When printing is completed and the test pattern is detected by the detection member after the apparatus is stopped, the control unit determines that the printing paper has slack. If the test pattern is not detected by the detection member after the printing is completed and the apparatus is stopped, the control unit determines that the printing paper has no slack.

When the control unit determines that there is slack, the slack correction mechanism separates the pressing member and the print head from the platen so that the print sheet is not pressed against the platen, and the print head is again pressed. Is pressed against the platen, the printing paper is pressed against the platen and the slack portion is pushed out in the printing paper feeding direction to correct the slack.

Therefore, even if the printing paper has slack, it can be automatically detected and corrected.

[0019]

Embodiments of the present invention will be described with reference to the drawings. The elements common to the drawings are designated by the same reference numerals. FIG. 1 is a schematic perspective view showing a multicolor thermal transfer recording apparatus according to one embodiment of the present invention, FIGS. 2 and 3 are explanatory views showing the relationship between a print sheet and a detection sensor according to one embodiment, and FIG. FIG. 5 is an explanatory view showing a part of the structure of an example multicolor thermal transfer recording apparatus, and FIG. 5 is a block diagram showing a control system of the multicolor thermal transfer recording apparatus of one embodiment. In FIG. 1, a multicolor thermal transfer recording apparatus 1 is provided with a print head 2 having a line type heating resistor, and a platen 9 is provided facing the print head 2. Brackets 3 are attached to both sides of the print head 2, and one end of a spring 10 is attached to one end 3 a of the bracket 3. The other end of the spring 10 is attached to a frame (not shown), and urges the bracket 3 in the direction of arrow A to press the print head 2 against the platen 9.

A cam 5 attached to the shaft 4 is in contact with the other end 3b of the bracket 3. A gear 6 is also attached to the shaft 4, and the gear 6 meshes with a gear 8 attached to a rotation shaft (not shown) of the print head pulse motor 7 and is driven by the print head pulse motor 7. The cam 5 is adapted to rotate. In addition,
The print head 2 is pressed by the platen 9 by the biasing force of the spring 10 when the lift of the cam 5 is at the minimum position, and resists the biasing force of the spring 10 when the lift of the cam 5 is at the maximum position. The bracket 3 rotates about the fulcrum 23 in the arrow B direction, and the print head 2 also rotates in the arrow B direction and separates from the platen 9.

Between the print head 2 and the platen 9, a printing paper 11 running in the direction of arrow C from a paper roll 13 is provided.
And the ink ribbon 12 which is supplied together with the printing paper 11, travels in the direction of arrow D from the supply roll 14 and is wound up by the winding roll 15. The ink ribbon 12 has a width substantially the same as the width of the printing paper 11, and
The transfer inks for the three primary colors for printing 6, 6, magenta 17, and cyan 18 are applied in a size slightly larger than the set size of the normal printing area. In addition, the ink ribbon 12
Are provided with ink ribbon marks 21 of different types for each color of the ink ribbon 12 in the vicinity of the front end of each color, which are detected by a detection sensor 22 provided in the running path of the ink ribbon 12. The ink ribbon 12 is conveyed by feeder rollers 24 and 25 provided on the traveling path of the ink ribbon 12.

The printing paper 11 is pressed against the platen 9 by pressure rollers 19 and 20 which rotate with the rotation of the platen 9. In addition, pressure roll
The ra 19 can be separated from the platen 9 by a contacting / separating mechanism (not shown) and moved to the position indicated by the broken line. A mechanism for bringing the print head 2 into and out of contact with the platen 9 and a mechanism for bringing the pressure roller into and out of contact with the platen 9 constitute a slack correction mechanism.

As shown in FIG. 2, a test pattern 27 is provided between the first page 11a and the second page 11b of the printing paper 11.
A margin 11c for printing is provided at a predetermined distance. Further, as shown in FIG. 1, a detection sensor 26, which is a detection member, is located downstream of the pressure roller 19 in the printing paper feeding direction.
Is provided. When the print sheet 11 is printed with a slack, the position of the detection sensor 26 is set after the print sheet 11 is printed, as shown in FIG.
Is discharged from the multicolor thermal transfer recording apparatus 1 for one page,
At a position where the test pattern 27 printed by the print head 2 is detected, and when the print paper 11 is printed without sagging, as shown in FIG. Is a position where the test pattern 27 printed by the print head 2 is not detected when one page is ejected from the multicolor thermal transfer recording apparatus 1.

The test pattern 27 is printed only when the operator turns on the power of the multicolor thermal transfer recording apparatus 1.
It is supposed to be done arbitrarily. The print start position 39 shown in FIG. 2 is the M position of the print sheet 11 shown in FIG. 4, and the leading end portion 40 of the first page 11a of the print sheet 11 is shown.
Is the N position of the printing paper 11 shown in FIG. Therefore, the printing paper 11 located downstream of the position N in the printing paper feeding direction is not used.

In FIG. 5, the control unit 41 includes an external device 3
An interface line 28 to which print data is inputted from 7 is connected. An I / O port 30 is connected to the control unit 41 by a common bus 29. The I / O port 30 has a print head 2, motor drivers 31, 32, and 3.
3, 34 and the detection sensors 22, 26 are connected, and these are controlled by the I / O port 30.

The motor driver 31 is connected to the paper motor pulse motor 35 for rotating the platen 9, and the motor driver 32 is a DC motor for the ink ribbon for rotating the feeder rollers 24, 25. Data 36 is connected. Further, the motor driver 33 is connected to the contact / separation pulse motor 37 of the print head 2, and the motor driver 34 is connected to the contact / separation pulse motor 3 of the pressure roller 19.
8 is connected.

Next, referring to FIGS. 1, 2, 3, 5, 9, 10 and 11, the operation of performing printing on the printing paper 11 in the above-described configuration will be described with reference to FIGS. 6, 7 and 8. An explanation will be given according to the flowchart. 6, FIG. 7, and FIG. 8 are flow charts showing the slack correction operation of the embodiment, and FIGS. 9, 10 and 11 are explanatory views showing the slack correction operation of the embodiment. In FIG. 1, first, the operator sets the printing paper 11 and the ink ribbon 12 in the multicolor thermal transfer recording apparatus 1, and when the power is turned on, the controller 4 is operated in step S1.
1, the motor driver 31 drives the paper feed pulse motor 35 to rotate the platen 9 in the direction of arrow E to convey the printing paper 11 from the direction of arrow C to the direction of arrow G. Then, the motor driver 32 drives the ink ribbon DC motor 36 to rotate the feeder rollers 24 and 25 to convey the ink ribbon 12 together with the printing paper 11 in the direction of arrow D for printing. Yellow-1 input from the external device 37 to the print area of the print sheet 11 by the head 2
6 is printed. In step S2, the control unit 41 controls the mode.
The print head pulse motor 7 is driven by the printer driver 33, the lift of the cam 5 is set to the maximum position, the print head is rotated in the direction of arrow B, and the print head 2 is separated from the platen 9.

In step S3, the control unit 41 drives the paper feed pulse motor 35 by the motor driver 31 to rotate the platen 9 in the arrow F direction, and moves the printing paper 11 from the arrow H direction to the arrow I direction. Return to and return to the initial position. At the same time, the motor driver 32 drives the ink ribbon DC motor 36 to drive the feeder roller 2.
4 and 25 are rotated to convey the ink ribbon 12 in the direction of arrow D. If the detection sensor 22 detects the ink ribbon mark 21 of the magenta 17 in step S4, the process proceeds to step S5. If the ink ribbon mark 21 of the magenta 17 is not detected, step S4 is performed. Return to.

In step S5, the control unit 41 controls the printing paper 1
When the magenta 17 is positioned in the print area of No. 1, the pulse driver for the print head is driven by the motor driver 33.
The printer 7 is driven, the lift of the cam 5 is set to the minimum position, the print head is rotated in the direction of arrow J, and the print head 2 is pressed against the platen 9. In step S6, the control unit 41 drives the paper feed pulse motor 35 by the motor driver 31 to rotate the platen 9 in the arrow E direction again to convey the print paper 11 from the arrow C direction to the arrow G direction. To do. And
DC motor 3 for the ink ribbon by the motor driver 32
6 is driven to rotate the feeder rollers 24 and 25 to convey the ink ribbon 12 together with the printing paper 11 in the direction of arrow D, and the print head 2 is placed in the printing area of the printing paper 11 to external device 37. The magenta 17 input from is printed.

In step S7, the control unit 41 drives the print head pulse motor 7 by the motor driver 33,
Set the cam 5 lift to the maximum position and move the print head to the arrow B
And the print head 2 is separated from the platen 9. In step S8, the control unit 41 causes the motor driver 31
Drives the paper feed pulse motor 35 to rotate the platen 9 in the direction of arrow F, and reversely feeds the printing paper 11 from the direction of arrow H to the direction of arrow I to return it to the initial position. At the same time, the motor driver 32 drives the ink ribbon DC motor 36 to drive the feeder rollers 24, 25.
Is rotated to convey the ink ribbon 12 in the direction of arrow D.

If the detection sensor 22 detects the ink ribbon mark 21 of cyan 18 in step S9, the process proceeds to step S10, and if the ink ribbon mark 21 of cyan 18 is not detected. If so, step S8
Return to.

In step S10, when the cyan 18 is positioned in the print area of the print paper 11 in step S10, the motor driver 33 causes the print head pulse motor to operate.
The print head 2 is rotated in the direction of arrow J with the lift of the cam 5 at the minimum position, and the print head 2 is pressed against the platen 9. In step S11, the control unit 41 controls the mode.
A pulse motor 35 for paper feed by a data driver 31.
Is driven to rotate the platen 9 in the direction of arrow E again to convey the printing paper 11 from the direction of arrow C to the direction of arrow G. Then, the DC driver for the ink ribbon is performed by the motor driver 32.
The printer 36 is driven to rotate the feeder rollers 24 and 25 to convey the ink ribbon 12 together with the printing paper 11 in the direction of the arrow D, and the printing head 2 puts the printing paper 11 in the printing area so that an external device can be used. The cyan 18 input from 37 is printed.

In step S12, the control unit 41 drives the print head pulse motor 7 by the motor driver 33, sets the lift of the cam 5 to the maximum position, and rotates the print head 2 in the direction of arrow B to print. The head 2 is separated from the platen 9. In step S13, the control unit 41 drives the paper feed pulse motor 35 by the motor driver 31 to rotate the platen 9 in the arrow E direction to move the print paper 11 from the arrow C direction to the arrow G direction by a predetermined amount. Transport.

In step S14, the control unit 41 drives the print head pulse motor 7 by the motor driver 33 to rotate the print head 2 in the arrow J direction with the lift of the cam 5 at the minimum position. The head 2 is pressed against the platen 9. In step S15, the control unit 41 causes the print head 2 to print a test pattern with cyan 18 outside the normal print area of the margin 11c between the first page 11a and the second page 11b of the print sheet 11. The length of the last color cyan 18 of the ink ribbon 12 is longer than that of the other yellow-16 and magenta 17 by the amount that the margin 11c of the printing paper 11 can be printed.

In step S16, the control unit 41 drives the print head pulse motor 7 by the motor driver 33, sets the lift of the cam 5 to the maximum position, and rotates the print head 2 in the direction of arrow B to print. The head 2 is separated from the platen 9. In step S17, the control unit 41 drives the paper feed pulse motor 35 by the motor driver 31 to rotate the platen 9 in the arrow E direction to convey the print paper 11 from the arrow C direction to the arrow G direction. . Then, the motor driver 32 drives the ink ribbon DC motor 36 to rotate the feeder rollers 24 and 25 to convey the ink ribbon 12 together with the printing paper 11 in the direction of arrow D. Then, the first page 11a of the printing paper 11 on which printing has been completed is discharged from the multicolor thermal transfer recording apparatus 1, and the driving of the multicolor thermal transfer recording apparatus 1 is stopped.

In step S18, the control unit 41 determines whether or not the detection sensor 26 has detected the test pattern 27, and when the detection sensor 26 detects the test pattern 27, the printing paper 11 has slack. If the detection sensor 26 does not detect the test pattern 27, it is determined that the printing paper 11 has no slack, and the slack detection operation is ended, and the second page 11b is printed.

As shown in FIG. 13, the printing paper 11
Printing starts with the slack in the platen 9
The feeding force is weak and the printing paper 11 sandwiched between the platen 9 and the printing head 2 is slipped without being conveyed, and as a result, slack is generated at the position shown in FIG. When the printing is performed with, the length h2 of the printing area becomes shorter in the printing paper feeding direction as shown in FIG. 3 than the length h1 of the printing area when there is no slack in the printing paper shown in FIG. . Therefore, when the printing paper 11 has slack, after the printing is completed, the detection sensor 26 causes the test pattern
27 is detected.

When the print sheet 11 has slack, when the print head 2 is separated from the platen 9, the slack portion is also separated from the platen 9, as shown in FIG. In step S19, the control unit 41 drives the pressure roller pulse motor 38 by the motor driver 34, and moves the pressure roller 19 in the direction of arrow K by a pressure roller contact / separation mechanism (not shown). Move to separate from platen 9. In step S20, the control unit 41 controls the motor driver 3
3 drives the print head pulse motor 7 to drive the cam 5
The print head 2 is rotated in the direction of arrow J with the lift of the print head 2 at the minimum position, and the print head 2 is pressed against the platen 9. Then, as shown in FIG. 10, the slack portion of the print sheet 11 is pushed out in the arrow L direction by the force of the print head 2 being pressed by the platen 9.

In step S21, the control unit 41 causes the motor driver 34 to operate the pulse motor 7 for the pressure roller.
The pressure roller 19 is pressed against the platen 9 by a pressure roller contact / separation mechanism (not shown). Then, as shown in FIG. 11, the slack of the print sheet 11 is corrected, the slack correction operation is completed, and the second page 11b is printed.

The printing of the test pattern 27 and the sag correction operation are performed not only when the power source of the multicolor thermal transfer recording apparatus 1 is turned on, but also when the constant number of sheets are printed. Alternatively, it may be detected whether or not the printing paper 11 has slack. As a result, not only the slack generated on the first page 11a of the printing paper 11 but also
The sagging that occurs inside can be corrected.

By printing the test pattern 27 outside the normal printing area of the printing paper 11, if there is no slack in the printing paper 11, as shown in FIG. 2, the first page of the printing paper 11 is printed. 11a is a normal print area length h1
Therefore, one page can be cut and used as it is, and the printing paper 11 is not wasted.

On the other hand, the test pattern 27 may be printed in the normal printing area. Test pattern in normal print area
If the print of the test pattern 27 is performed, the first page 11a on which the test pattern 27 is printed is wasted, but since it is in the normal print area, it is necessary to enlarge the print head 2 in the direction orthogonal to the print sheet feeding direction. In addition, the ink ribbon 12 is not wasted because it is not necessary to increase or increase the width of the ink ribbon 12.

[0043]

Since the present invention is configured as described above, it has the following effects. It automatically detects whether or not there is slack in the print paper, and if there is slack, it automatically corrects it, eliminating the need for the operator to reset the print paper, and also improving print quality easily. Can be undone.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing a multicolor thermal transfer recording apparatus according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a relationship between a print sheet and a detection sensor according to an embodiment.

FIG. 3 is an explanatory diagram illustrating a relationship between a print sheet and a detection sensor according to an embodiment.

FIG. 4 is an explanatory view showing the structure of a part of the multicolor thermal transfer recording apparatus of one embodiment.

FIG. 5 is a block diagram showing a control system of a multicolor thermal transfer recording apparatus of one embodiment.

FIG. 6 is a flowchart showing a slack correction operation according to an embodiment.
It is

FIG. 7 is a flow chart showing a sagging correction operation according to an embodiment.
It is

FIG. 8 is a flow chart showing a slack correction operation of one embodiment.
It is

FIG. 9 is an explanatory diagram showing a sagging correction operation according to an embodiment.

FIG. 10 is an explanatory diagram showing a sag correcting operation of the embodiment.

FIG. 11 is an explanatory diagram showing a sag correcting operation according to an embodiment.

FIG. 12 is a schematic perspective view showing a conventional multicolor thermal transfer recording apparatus.

FIG. 13 is an explanatory diagram showing a slack of a conventional printing paper.

FIG. 14 is an explanatory diagram showing a slack of a conventional printing paper.

[Explanation of symbols]

 1 Multicolor Thermal Transfer Recording Device 2 Print Head 9 Platen 11 Printing Paper 12 Ink Ribbon 19 Pressure Roller 20 Pressure Roller 26 Detection Sensor 27 Test Pattern 41 Control Section

Front page continuation (72) Inventor Shuichiro Ogata 1-7-12 Toranomon, Minato-ku, Tokyo Oki Electric Industry Co., Ltd.

Claims (3)

[Claims] 1. A printer for performing printing by a print head, which presses and feeds a printing paper to a platen by a pressing member, and presses an ink ribbon superposed on the printing paper and fed to the platen. A print head that prints a test pattern on the print paper at a specified distance in the feeding direction, a detection member that detects the printed test pattern, and whether the print paper has slack depending on the detection result of the detection member. A printer provided with a control unit for judging. 2. The control unit determines that there is slack in the print paper when the test pattern is detected by the detection member, and determines that the print paper is slack when the test pattern is not detected by the detection member. The printer according to claim 1, wherein a judgment is made. 3. The pressing member and the print head are separated from the platen so that the print paper is temporarily not pressed against the platen, and the print head is pressed against the platen to press the print paper against the platen again. 3. The printer according to claim 1, further comprising a slack correction mechanism for correcting the slack by pushing the slack portion in the feeding direction.