JPH10120240A - Printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printer that can convey paper after recording with accuracy and hold stable recording quality over a long period of time. SOLUTION: This printer has a paper feed roller 6 rotatory-driven to convey paper 4 into a recording position PP, a recording head 3 that can be brought into contact with and separated from a recording platen 2, a discharge roller 9 for discharging the paper 4 after recording and a movable paper veil 10 disposed opposedly to the discharge roller 9 and provided with a paper contact part 14 that can be brought into contact with and separated from a recorded paper 4 part having passed the discharge roller 9 in order to control the attitude of the recorded paper 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer,
In particular, the present invention relates to a printer capable of accurately transporting a sheet after recording and maintaining stable recording quality for a long period of time.

[0002]

2. Description of the Related Art In general, various types of printers such as a thermal transfer printer, an ink jet printer, a laser beam printer, and the like which record characters and figures on paper such as plain paper, OHP paper, cardboard, and postcards have high recording quality. For reasons such as low noise, low cost, and ease of maintenance, they are used as output devices such as computers, word processors, and facsimile machines.

[0003] A serial type thermal transfer printer will be described as an example of such a conventional printer. The conventional thermal transfer printer is configured to reciprocate along a platen, and ink of a desired color is formed on a base film. It has a carriage on which a ribbon cassette having an ink ribbon formed thereon can be mounted, and a thermal head as a recording head in which a plurality of heating elements that move toward and away from a platen are arranged on the carriage. The paper and the ink ribbon are supported in front of the platen, and the ink ribbon is fed while the thermal head pressed against the platen via the paper and the ink ribbon is reciprocated along with the carriage along the platen, Based on the recorded information, a plurality of heating elements By selectively heating have been, the ink of the ink ribbon is partially melted and transferred to a predetermined recording position of the paper, is configured to perform recording of an image, such as desired characters on the paper.

In such a general printer, the paper fed from a paper feed unit is sandwiched between a paper feed roller and an auxiliary roller which abuts on the paper feed roller while rotating. The sheet is conveyed to a recording position by rotating a roller, and the sheet after recording is discharged to the outside by rotating a sheet discharge roller.

[0005]

However, in the above-described conventional thermal transfer printer, the printing after recording is performed due to the squeezing of the paper due to the movement of the thermal head in the pressed state, the evaporation of the water on the paper surface due to the heat generated by the heating element, and the like. Paper has a problem that curls are formed with the recording surface inside. The size of the curl formed on this paper is
There is a problem in that the higher the recording duty (recording density) such as the recording pattern and the recording density, and the larger the color recording in which the overlapping recording is performed at the same recording position than in the monochrome recording.

Further, curl formed on a sheet after recording is generated by heating at the time of fixing toner in an electrophotographic printer, and is generated by evaporation of water after ink adhesion in an ink jet printer. .

If the size of the curl is large, the curl formed on the paper after recording is bulky when the paper after recording is overlaid, and the information recorded on the paper is difficult to confirm and is difficult to handle. There was a problem.

The applicant of the present invention has proposed Japanese Patent Application No. Hei 6-323254 (Japanese Unexamined Patent Application Publication No. 8-174) to address such a problem.
947), a support platen for supporting a curled sheet after recording, a carriage reciprocally movable along the support platen, and a support platen on the carriage, downstream of the recording position in the sheet transport direction. A printer provided with a curl correcting device which is disposed so as to face the paper and has a pressing member which presses the paper so as to remove the curl formed on the paper with the movement of the carriage. .

According to the printer adopting such a configuration, when the recording sheet passes through the curl correcting device, the pressing member provided on the reciprocating carriage moves with the movement of the carriage. The paper is moved while pressing the back surface opposite to the recording surface of the curled paper to generate a new curl opposite to the curl formed by recording on the paper, thereby effectively correcting the curl of the curled paper. It has an excellent effect that it can be performed.

In a printer having the above-described curl correcting device, a support platen is generally disposed downstream of a recording position in a sheet conveying direction.
The leading edge of the recorded paper collides with the support platen and the paper cannot be transported properly.In other words, the leading edge of the recorded paper collides with the support platen during a line feed operation during recording, and the paper is transported. However, there is a problem in that the line feed amount is reduced and black streaks are generated between lines, resulting in a decrease in recording quality or a difference in recording quality for each sheet.

[0011] Such a problem is common not only when the printer has a curl correcting device but also when there is an obstacle ahead in the conveying direction of the sheet after recording.

[0012] Therefore, there is a demand for a sheet capable of accurately conveying a sheet after recording and maintaining stable recording quality for a long period of time.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to provide a printer capable of accurately transporting a sheet after recording and maintaining stable recording quality for a long period of time. And

[0014]

According to a first aspect of the present invention, there is provided a printer comprising: a paper feed roller which is driven to rotate and conveys a sheet to a recording position; A recording head that can be moved toward and away from the recording platen, a paper discharge roller that discharges the paper after recording, and the paper discharge roller of the paper after recording to control the orientation of the paper after recording. The present invention is characterized in that a movable paper bale is provided so as to have a paper abutting portion that can be brought into contact with and separated from a portion thereof and is disposed so as to face the paper discharge roller.

By adopting such a configuration, the paper bale controls the posture of the paper sheet after recording by moving its paper contact portion to or away from a portion of the paper sheet that has passed through the paper discharge rollers. As a result, it is possible to prevent the leading end of the printed sheet from colliding with an obstacle located forward in the transport direction of the printed sheet.

According to a second aspect of the present invention, there is provided a printer according to the first aspect, wherein the paper bale does not transmit at least a conveying force of the discharge roller to a sheet after recording. The standby position where the sheet contact portion is positioned so as to be in a state, and the leading end of the sheet after recording in a state in which the non-transmission state of the conveying force of the sheet discharging roller with respect to the sheet is maintained. The paper contact portion is positioned such that the paper contact portion is positioned so as to prevent collision with an obstacle located in front of the paper, and the paper contact portion is configured to transmit the conveyance force of the paper discharge roller to the paper. The point is that it is movably formed so as to be able to selectively take any one of the three positions with the conveying force transmission position where the portion is located.

By employing such a configuration, the paper bale can be selected at an appropriate position according to the position of the paper, so that the transport of the paper after recording can be performed more accurately.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to an embodiment shown in the drawings.

FIGS. 1 to 3 show the structure of a main part of an embodiment of a printer according to the present invention. FIG. 1 is an explanatory view showing a paper bale standby position, and FIG. FIG. 3 is an explanatory diagram illustrating a collision prevention state, and FIG. 3 is an explanatory diagram illustrating a position at which a paper bale conveys a conveying force.

In the printer of the present embodiment, a paper bale for preventing fluttering of paper is originally provided in a serial type thermal transfer printer equipped with a known curl correcting device so as to have a special configuration. Things. Therefore, a detailed description of the printer and the curl correction device will be omitted.

As shown in FIG. 1, inside the printer 1 of this embodiment, a plate-like recording platen 2 is disposed so that its recording surface 2a is substantially vertical.
A plurality of heating elements (not shown) are provided in front of the recording platen 2 shown on the right side of FIG. 1 and opposed to the recording platen 2 by a drive mechanism (not shown). The thermal head 3 is arranged as a recording head in which (1) is arranged. The contact position between the thermal head 3 and the recording platen 2 in a head-down state (not shown, FIGS. 1 to 3 show a head-up state) in contact with the recording platen 2 is the recording position. It is PP. Further, between the recording platen 2 and the thermal head 3, a sheet 4 and an ink ribbon (not shown) are supplied in order from the recording platen 2 side.

The thermal head 3 is provided on a recording carriage 5 which is reciprocally movable along a recording surface 2a of a recording platen 2 by a stepping motor (not shown). A ribbon cassette (both not shown) having an ink ribbon formed by applying ink of a desired color to a base film can be mounted.

An arrow A in FIG.
On the upstream side (lower in FIG. 1) in the transport direction of the paper 4 indicated by,
A paper feed roller 6 that conveys the paper 4 toward the recording position PP at a predetermined speed is provided. The paper feed roller 6 is driven to rotate by a stepping motor (not shown). An auxiliary roller 7 abutting on the outer peripheral surface of the paper feed roller 6 is provided on the right side of the paper feed roller 6 in FIG.
Are arranged rotatably, and the auxiliary roller 7 is driven to rotate by the paper feed roller 6.

That is, the paper 4 can travel upward from below as indicated by an arrow A in FIG. 1 so as to be sandwiched between the paper feed roller 6 and the auxiliary roller 7 constituting the paper feed mechanism 8. It has been.

An arrow A in FIG.
On the downstream side (upper in FIG. 1) in the transport direction of the paper 4 indicated by,
The paper is fed with a driving force of a drive motor (not shown) for discharging the paper 4 to the outside so as to be located on the side opposite to the recording surface 4a side of the paper 4 on which recording is completed and discharged from the recording position PP to the outside. A discharge roller 9 that is driven to rotate in conjunction with the roller 6 is provided.
A paper veil 10 also serving as a guide is disposed so as to be substantially opposed to the paper 4 via the paper 4 and to be positioned on the recording surface 4a side of the paper 4 on which recording has been completed.

The paper veil 10 has a base 12 attached to a support shaft 11 disposed substantially parallel to the recording platen 2, and extends toward a free end side of the base 12 shown on the left side of FIG. 1. And the operating arm 13 extended. The free end of the operating arm 13 serves as a paper contact portion 14 that can contact and separate from a portion of the recorded paper 4 that has passed through the paper discharge roller 9 in order to control the attitude of the recorded paper 4. A plurality of ribs (only some of which are shown) 15 functioning as a paper ejection guide are formed on the lower surface of the paper veil 10. Further, the support shaft 11 has both ends in the longitudinal direction bent substantially in a crank shape (not shown), and the paper contact portion 14 of the paper bale 10 is ejected by reference numeral B in FIG. The paper roller 9 is formed so as to be rotatable around a rotation center position located on the right side of the axis of FIG.

That is, the paper bale 10 is driven by a driving mechanism having a lever or a cam (not shown) so as to rotate about a rotation center position indicated by a reference symbol B, and a standby position shown in FIG. , And a movable position so as to be able to selectively take any one of three positions of a collision prevention position shown in FIG. 2 and a conveying force transmitting position shown in FIG. The paper bale 10 is driven by a known paper detecting unit (not shown), a ROM (not shown), a ROM storing a program, etc., based on recording information, an operation state, and the like.
A control unit including a memory such as an M determines the position of the leading end of the sheet 4 and controls the operation timing.

Further, the paper bale 10 may be one in which the base 12 and the operating arm 13 are divided into a plurality of pieces along the width direction of the sheet 4 perpendicular to the transport direction indicated by the arrow A.

On the downstream side (upper side in FIG. 1) of the paper 4 in the transport direction of the paper 4 indicated by the arrow A in FIG. A well-known curl correction device 21 is disposed on the back side of the recording surface 4a of the sheet 4 so that the support platen 20 contacts the correction plate 21 and the correction head (not shown).

The printer 1 equipped with the curl correction device 21 may be, for example, an electrophotographic printer or an ink jet printer, and is not particularly limited to the serial type thermal transfer printer of the present embodiment.

Next, the operation of the present embodiment having the above-described configuration will be described.

The recording operation of the printer 1 according to the present embodiment is as follows. First, based on a control command sent from a control unit (not shown), the paper 4 supplied from a paper feeding unit (not shown) such as a paper feeding cassette. Is started with the driving force of a paper feed motor such as a stepping motor (not shown).

Next, as shown in FIG. 1, the paper 4 is nipped and conveyed between a paper feed roller 6 and an auxiliary roller 7 which comes into contact with the paper feed roller 6, and the head of the paper 4 for recording is transported. Make a delivery. At this time, the leading end of the sheet 4 conveyed by the sheet feed roller 6 on the leading side in the conveying direction indicated by the arrow A in FIG. 1 is positioned between the recording surface 2 a of the recording platen 2 in the head-up state and the thermal head 3. , And in front of the paper discharge roller 9, more specifically, the transport direction indicated by the arrow A of the rib 15 functioning as a paper discharge guide formed on the lower surface of the paper bale 10 located in the standby state shown in FIG. 1. Stops at a position slightly beyond the trailing end located downstream of the sheet 4, and the first recording portion of the recording surface 4a of the sheet 4 is located at the recording position PP. Further, a known ink ribbon (not shown) is supplied between the paper 4 and the thermal head 3.

Next, the paper 4 is placed on the recording platen 2.
The thermal head 3 is brought into contact with the thermal head 3 via the ink ribbon to bring the head down, and while moving the recording carriage 5 along the recording platen 2, an ink ribbon (not shown) is fed out. The first line is recorded by selectively generating heat, and then the thermal head 3 is set to the head-up state, and the paper feed motor is driven to perform a paper feed operation for one line, for example, a line feed. After that, recording and line feed are sequentially performed.

In the printer 1 according to the present embodiment, the recording and the line feed are repeated in order, and the leading end of the sheet 4 collides with the supporting platen 20 constituting a part of the curl correcting device 21 beyond the sheet discharging roller 9. When the control unit (not shown) detects a possible position from the recording information and the line feed amount, the paper bale 10 is driven by a drive mechanism (not shown),
As shown in FIG. 2, the paper veil 10 rotates counterclockwise about the rotation center position C by the angle θ1 and is located at the collision prevention position.

In the collision prevention position of the paper bale 10, as shown in FIG. 2, the paper abutting portion 14 of the paper bale 10 abuts on the recording surface 4a of the paper 4 after recording, and the leading end of the paper 4 is moved. 2 and the paper 4
The conveyance force of the paper discharge roller 9 that rotates in conjunction with the paper feed roller 6 by contacting the surface located on the side opposite to the recording surface 4a with the paper discharge roller 9 with a weak force. The posture of the paper 4 is controlled so that the paper 4 is not transmitted to the paper 4.

The paper bale 10 is located behind the support platen 20 which constitutes a part of the curl correction device 21 in which the leading end of the paper 4 after recording is located on the downstream side (upward in FIG. 1) in the transport direction indicated by the arrow A. As a result, the paper bale 10 holds the curl correcting device as an obstacle such that the leading end of the recorded paper 4 is located downstream in the transport direction indicated by the arrow A during the paper feeding operation. It is possible to reliably prevent collision with the rear end of the support platen 20 which forms a part of the support platen 21. For reference, FIG. 4 shows a collision state in which the leading end of the recorded paper 4 collides with the rear end of the support platen 20 when the paper 4 is transported while the paper bale 10 is located at the standby position. .

Next, when the control unit (not shown) detects the position where the leading end of the sheet 4 exceeds the rear end of the support platen 20 from the recording information and the line feed amount, the recording unit and the line feed are repeated in order, and the driving mechanism (not shown) The paper bale 10 is driven, the paper bale 10 rotates clockwise by the angle θ1 and returns to the standby position shown in FIG. 1, and is located on the opposite side of the recording surface 4a of the paper 4 after recording during the paper feeding operation. The state in which the surface does not contact the paper discharge roller 9, that is, the paper discharge roller 9
The posture of the paper 4 is controlled so as to maintain the non-transmission state where the conveyance force is not transmitted.

Next, the recording and the line feed are repeated in order, and the position where the rear end of the paper 4 has passed the paper feed roller 6, that is,
When a control unit (not shown) detects a position beyond the contact portion between the paper feed roller 6 and the auxiliary roller 7 from the recording information and the line feed amount, the paper bale 10 is driven by a drive mechanism (not shown).
As shown in FIG. 3, the paper bale 10 rotates counterclockwise about the rotation center position C by an angle θ2 larger than the angle θ1 and is located at the conveyance force transmission position.

As shown in FIG. 3, the paper abutting portion 14 of the paper bale 10 is in contact with the recording surface 4a of the paper 4 after recording at the position where the paper bale 10 is conveyed by the transport force. Is moved to the left side in FIG. 2 more than when it is moved to the collision prevention position, and the recording surface 4a of the paper 4 is
The paper 4 is so contacted that the surface located on the opposite side of the paper 4 contacts the paper discharge roller 9 with a large force and the conveyance force of the paper discharge roller 9 that is driven to rotate in conjunction with the paper feed roller 6 can be transmitted to the paper 4. Attitude can be controlled.

The paper veil 10 keeps the transmission state until all the recording on the paper 4 is completed and the trailing end of the paper 4 after the recording has passed the conveying roller 9. As a result, the paper veil 10 is The posture of the paper 4 can be controlled so as to surely carry and discharge the paper 4.

When the control unit (not shown) detects the ejection of the paper 4 after recording by a sensor (not shown) or the like,
Position the paper bale 10 at the standby position, and
To prepare for the record.

Further, when the recording paper 4 passes through the curl correcting device 21, a new curl in the opposite direction to the curl formed by the recording is generated, and the curl formed by the recording is renewed. By canceling out due to the curl, the curl of the paper 4 formed by recording is easily corrected, and when the paper 4 after recording is piled up,
A problem that information recorded on the paper 4 is difficult to confirm and difficult to handle can be reliably removed.

As described above, in the printer 1 according to the present embodiment, any one of the three positions of the standby position, the collision prevention position, and the conveyance force transmitting position can be selectively set around the rotation center position C. Paper veil 1 movably formed
By selecting the position of the paper bale 10, the paper abutting portion 14 of the paper bale 10 is brought into contact with and separated from the portion of the paper 4 after recording that has passed through the paper discharge roller 9, and the position after recording is The attitude of the paper 4 can be easily controlled, and as a result, the paper 4 after the recording can be reliably transported.

In the paper veil 10 of the printer 1 according to the present embodiment, in the collision prevention position, recording is performed by lightly contacting the paper contact portion 14 with the portion of the paper 4 after recording that has passed the paper discharge roller 9. A support platen 2 serving as an obstacle in which the leading end of the succeeding sheet 4 is located forward in the transport direction indicated by the arrow A.
0 can reliably be prevented from colliding with a conventional paper sheet caused by the paper feed operation, that is, the leading edge of the recorded paper 4 colliding with the support platen 20 during the line feed operation during recording. In this way, it is possible to reliably prevent the inconvenience that the line feed amount is reduced due to the conveyance of the sheet 4 and the recording quality is reduced, and that the recording quality is different for each sheet 4.
Can be reliably performed with high accuracy, and stable recording quality can be reliably maintained over a long period of time.

Further, in the paper bale 10 of the printer 1 according to the present embodiment, the paper abutment portion 14 is brought into strong contact with a portion of the paper 4 after recording, which has passed through the paper discharge roller 9, at the conveying force transmitting position. As a result, the conveying force of the discharge roller 9 can be reliably transmitted to the recording paper 4 that has passed through the paper feed roller 6, so that the recording paper 4 can be accurately conveyed and reliably discharged. As a result, when the trailing edge of the paper 4 passes the paper feed roller 6, the load for transporting the paper 4 added to the paper 4 is eliminated, so that the line feed amount becomes large and the inconvenience that white streaks occur between the lines is also ensured. Can be prevented.

That is, the paper bale 10 of the printer 1 of the present embodiment is formed so as to be movable so as to be able to selectively take any one of three positions, a standby position, a collision prevention position, and a conveying force transmitting position. The transport of the paper 4 after recording can be performed more reliably and accurately, and the inconvenience caused by the poor transport accuracy of the paper 4 can be reliably removed, and stable recording quality can be reliably maintained for a long period of time. .

Further, according to the printer 1 of the present embodiment, by rotating the paper bale 10,
Since the movement trajectory of the leading end of the paper 4, that is, the transport path of the paper 4 can be changed by controlling the attitude of the paper 4 after recording, the degree of freedom in designing the printer 1 increases.

It should be noted that the present invention is not limited to the above-described embodiment, but can be modified as needed.

[0050]

As described above, according to the printer of the present invention, a movable paper bale having a paper abutting portion which can be brought into contact with and separated from a portion of a printed paper that has passed through a paper discharge roller is arranged. With this simple configuration, it is possible to easily control the orientation of the sheet after recording passing through the sheet ejection roller,
As a result, the conveyance of the paper after recording is performed with high accuracy,
This provides an extremely excellent effect that stable recording quality can be reliably maintained for a long period of time.

According to the printer of the present invention, the paper bale is formed so as to be movable so as to be able to selectively take any one of three positions of a standby position, a collision prevention position and a conveying force transmitting position. This provides an extremely excellent effect that the subsequent conveyance of the sheet can be performed more reliably and accurately, and stable recording quality can be reliably maintained for a long period of time.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a configuration of a main part of a printer according to an embodiment of the present invention at a paper bale standby position;

FIG. 2 is a view similar to FIG. 1, showing a configuration of a main part of the printer in FIG. 1 at a paper bale collision prevention position.

FIG. 3 is a view similar to FIG. 1, showing a configuration of a main part of the printer of FIG. 1 at a paper bale conveying force transmission position.

FIG. 4 is a reference explanatory diagram illustrating a collision state in which the leading edge of a sheet after recording collides with the trailing edge of a support platen.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printer 2 Recording platen 2a Recording surface 3 Thermal head (as recording head) 4 Paper 6 Paper feed roller 9 Discharge roller 10 Paper veil 11 Support shaft 12 Base 13 Working arm 14 Paper contact part 20 Support platen 21 Curl straightening Device PP Recording position A Transport direction of paper B Rotation center position of paper bale

Claims (2)

[Claims] 1. A paper feed roller which is rotated and conveys a sheet to a recording position, a recording head which can be brought into contact with and separated from a recording platen, a discharge roller which discharges a sheet after recording, and A movable sheet disposed so as to be able to contact and separate from a portion of the sheet after recording that has passed through the sheet discharging roller in order to control the position of the sheet, and to be disposed so as to face the sheet discharging roller. A paper veil. 2. A standby position in which the paper bale is positioned so that at least the paper discharge roller conveys a conveying force of the paper discharge roller to a paper after recording, in a non-transmission state.
In a state in which the conveyance force of the discharge roller is not transmitted to the sheet, the sheet is formed so as to prevent the leading end of the sheet after recording from colliding with an obstacle located forward in the direction of conveyance of the sheet after recording. One of three positions is selected: a collision prevention position where the contact portion is located, and a conveyance force transmission position where the sheet contact portion is located such that the conveyance force of the discharge roller to the sheet is transmitted. 2. The printer according to claim 1, wherein the printer is formed so as to be movable.