JP2001130072A - Dust removing card holder of printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such a problem that a cleaning maintenance interval is short because dust adheres to and accumulate on the surface of the sensor mounted in a card holder. SOLUTION: A projected surface 3 having a horizontal U-shape opened on the suction side of a medium is formed to a card holder of a part where a medium position detecting sensor 5 is mounted and dust bonded to the surface 9 of the sensor is always removed by air streams generated during medium feed operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dust removing card holder of a printer, and more particularly to a dust removing card holder of a printer having a sensor for detecting a medium.

[0002]

2. Description of the Related Art Conventionally, in a sheet width detecting means for detecting a sheet on a platen, one end of the sheet is first detected by various sensors, and the carriage is moved to the other end by using this as a trigger to detect the amount of movement. The amount of movement of the carriage is converted into a distance to calculate the paper width. Then, the calculation result is compared with the data amount per line from the higher-level device. If the data amount from the higher-level device is larger than the sheet width, the printing operation is interrupted or a line feed is performed by an external command or the like. It is possible to effectively prevent the printing operation from being performed for other than the above.

[0003] A dust removal card holder of a conventional printer will be described in detail with reference to the drawings.

FIGS. 3A to 3C are a perspective view, a sectional view, and a side view showing a first conventional example. (See, for example, JP-A-08-002066).

Reference numeral 101 denotes a cylindrical platen, and reference numeral 102 denotes a print head for performing a predetermined printing operation on a paper medium P. The platen 101 functions to hold the sheet medium P and perform sheet feeding and backup of printing. Reference numeral 103 denotes a carriage. This carriage 1
Reference numeral 03 denotes a card holder 104 and an ink ribbon cartridge 105 which are disposed so as to surround the print output surface of the print head 102, and are mounted so as to be able to reciprocate in parallel with the platen 101 described above. Symbol A indicates an ink ribbon.

The card holder 104 has a relatively large through hole 104A at the center, and the tip of the print head 102 is disposed in the through hole 104A. On the platen 101 side of the through hole 104A, a ribbon protection mask 104B is attached so as to cover the entire surface of the through hole 104A. Then, the ribbon protection mask 104
A printing operation hole 104Ba having a size corresponding to the print output surface of the print head 102 described above is provided at the center of B.

The printing action hole 104Ba is formed in a diamond shape. The card holder 104 is provided with an optical sensor 106 that detects the paper medium P and the platen 101 and outputs an identification signal. This optical sensor 106 is mounted above the print head 102. Symbol 104a
Denotes a paper detection hole for detecting the presence or absence of the paper medium P.

The carriage 103 on which the print head 102, the card holder 104, and the ink ribbon cartridge 105 are mounted has a guide shaft 107A and a holding stay 10A.
It is guided and supported by 7B, and is provided so as to be movable in a direction parallel to the platen 101. This carriage 10
Reference numeral 3 is driven by a carrier drive motor 108 via a timing belt 108A, so that its moving force is urged.

The optical sensor 106 is connected to the cable 10
The detection information of the paper medium P is sent to the control board via 6A.

FIGS. 4A and 4B are a top view and a plan view showing a second conventional example. (For example, see JP-A-04-3
No. 55172). In this example, printing position sensors are provided on the left and right sides of the card holder, and the printing position is intended to be accurately determined without being affected by the conveyance deviation of the medium.

The print head 201 and the card holder 20
3 is mounted on the carriage 202, and the print position detection sensors 204a and 204b
1 is mounted on the card holder 203.
The carriage 202 is guided by a spacing shaft 205 and a guide shaft 206 and can move left and right.

The drive transmission belt 209 is connected to the carriage 20
2 and is connected to a drive motor and a pulley (not shown). As a result, the carriage 202 moves left and right by the rotation of the drive motor, so that the print head 201 and the card holder 203 mounted thereon and the print position detection sensors 204a and 204b similarly move left and right.

When the passbook 207 is conveyed onto the platen 208, the platen 208 can be moved up and down by a gap detection mechanism (not shown) so as to secure an optimum gap for printing.

When the passbook 207 is sucked through the insertion slot 217, the pair of upper and lower transport rollers 210a and 201
b, 211a, 211b, 212a, 212b, are conveyed and positioned by the conveyance positioning sensors 213, 214, and stop at the print position.

When the passbook 207 is conveyed to the printing position, it is regulated to some extent in the left-right direction by the frames 216 and 215. The upper and lower printing positions are determined by a specified number of steps after the upper end of the passbook 207 is detected by the transport positioning sensor 214.

Further, when printing from left to right, the print position is determined by the specified number of steps after the print position detection sensor 204b detects the left end of the passbook 207.

Similarly, when printing is performed from right to left, the printing position is determined by a specified number of steps after the printing position detection sensor 204a detects the right end of the passbook 207.

FIGS. 5A and 5B are a bottom view and a side view showing a third conventional example, and FIGS. 6A and 6B are side views showing a use state. (For example, Japanese Patent Application Laid-Open
No. 9660).

In the case where the surface of the card holder near the printing hole for holding the medium is flat and the medium is positioned on the same plane as the plane for horizontal movement, the medium such as a passbook is When printing, the open and swollen part of the passbook rises into the printing hole, and the printing ink is not adhered or the medium cannot be forcibly pressed. Becomes thinner.

In the figure, reference numeral 302 denotes a platen, and a print head 303 is provided facing the platen 302, and feed rollers 305, 306 and tension rollers 307, 308 for feeding and discharging the print medium 304 are provided in close proximity to these. Is provided.

A card holder 301 is provided near the print head 303. A projection 309 is provided on the surface (lower surface) of the card holder 301 on the side of the print medium 304.
Is provided. That is, two projections are provided on the lower surface of the card holder 301 at the side of the printing hole 310. The protrusion 309 is located on the near side and the feed side with respect to the traveling direction of the print medium 304, and is arranged at an appropriate length in parallel with the longitudinal direction of the card holder 301.

Here, the projection 309 protrudes toward the platen 302 from the horizontal movement surface.

As shown in FIG. 6A, the print medium 304
To the feed roller 305 and the tension roller 307.
To pass between the card holder 301 and the platen 302 by the feed roller 306 and the tension roller 3.
08 and the print medium 304
Position on the lower surface of.

Next, as shown in FIG. 6B, the platen 302 is raised in the direction B, and printing is performed after the print medium 304 is forcibly pressed by the projections 309 of the card holder 301 and the platen 302.

FIGS. 7A and 7B are a side view and a partial perspective view showing a fourth conventional example. (See, for example,
-162397).

When printing with a high print density is performed, the ink printed on the paper P is rubbed by the paper pressing surface 412 of the card holder 411 before the ink is sufficiently dried, that is, the paper P is stained with ink (that is, smudge is generated). appear)
Sometimes.

The occurrence of such smudges is a problem that cannot be overlooked at present, since high-density printing such as graphic printing is often performed.

As shown in FIG. 7A, this printer includes a platen (printing stand) 402, a carrier 403, a print head 4
04 and a card holder 411.

Here, the paper holding surface 412 of the card holder 411 extends in the carrier moving direction (in the direction perpendicular to the paper surface in the drawing) in correspondence with the print use area AR of the platen 402 and is located on the paper use area AR. A concave 415 is provided.

The concave portion 415 of the card holder 411 is formed in an arc shape so that the end of the sheet fed to the platen 402 is not caught. More specifically,
Considering that the print head 404 has 24 pins and the printable width is about 3.25 mm, the width dimension W of the concave portion 415 is
mm. Further, as the depth H of the concave portion 415,
According to various experiments, 0.3 mm was selected as the depth at which the paper could pass without difficulty.

Next, the operation will be described. In this printer, the sheet P sent to the platen 402
In the print use area AR of the platen 402,
Printing is performed by a print head 404 that moves together with the carrier 403. At this time, the paper P is
Paper holding surface 412 of card holder 411 that moves synchronously with
, And is prevented from floating from the platen 402.

Here, since the card holder 411 moves with the concave portion 415 of the paper pressing surface 412 separated from the printing portion of the paper P, the ink printed on the paper P for printing with a high print density or the like is provided. Even if the ink is not sufficiently dried, the ink does not adhere to the concave portion 415 of the paper pressing surface 412 as well as other portions. This allows
The generation of smudge is prevented.

The paper holding surface 412 of the card holder 411
The card holder 411 is provided with a concave portion 415 extending in the carrier moving direction corresponding to the print use area AR of the platen 402 and recessed with respect to the print use area AR. The concave portion 415 moves while being separated from the paper print portion. As a result, even when printing with a high print density or the like is performed, ink does not adhere to the concave portion 415 of the paper pressing surface 412 of the card holder 411 as well as other portions, thereby preventing generation of smudge.

Further, since the concave portion 415 of the card holder 411 is formed in an arc shape, printing can be performed smoothly without the edge of the sheet P fed into the platen 402 being caught in the concave portion 415.

The concave portion 415 of the card holder 411 may have a boat shape (for example, an inclination angle θ = 30 °, a bottom width W = 4 mm, and a depth H = 0.3 mm) in addition to the arc shape.

[0036]

In the card holder of the above-mentioned conventional printer, the surface of the print position detection sensor may be scratched, ink, dust, etc., and the sensor level may drop rapidly. Had to be done. If the sensor surface position of the print position detection sensor is flush with the card holder, scratches and ink etc. are likely to adhere to the passbook, and if the sensor surface position is higher than the card holder to prevent this, This is because dust adheres and accumulates on the surface.

It is an object of the present invention to provide a card holder which is maintenance-free without adding a complicated dust removing mechanism to dust adhering to a medium position detecting sensor mounted inside.

[0038]

According to a first aspect of the present invention, there is provided a dust removing card holder for a printer which presses a print medium with a card holder, performs printing with a printer head and a platen, and detects a position of the print medium. A projection provided in a vicinity of a detection hole of the sensor on a print medium side surface of the card holder.

In a dust removing card holder for a printer according to a second aspect of the present invention, in the first aspect, the protrusion has a U-shape.

A dust removing card holder for a printer according to a third aspect of the present invention is the dust removing card holder according to the first aspect, wherein the protrusion has a V-shape.

According to a fourth aspect of the present invention, in the dust removing card holder of the printer according to the first aspect, the protrusion is U-shaped.

According to a fifth aspect of the present invention, in the dust removing card holder for a printer according to the first aspect, the opening of the U-shaped projection is arranged in the direction in which the printing medium enters.

According to a sixth aspect of the present invention, in the dust removing card holder for a printer according to the first aspect, the opening of the V-shaped projection is arranged in the direction of entry of the printing medium.

A dust removing card holder for a printer according to a seventh aspect of the present invention is the printer according to the first aspect, wherein the opening of the U-shaped projection is arranged in a direction in which the print medium enters.

[Operation] The dust removal card holder of the printer of the present invention has a convex shape opened toward the medium suction side so that air does not stay around the medium position detection sensor surface. At the time of the spacing operation, airflow is generated around the sensor surface, so that dust does not adhere or accumulate.

[0046]

Next, the present invention will be described in detail with reference to the drawings.

FIGS. 1A and 1B are a front view and a bottom view showing an embodiment of the present invention. FIG. 1 (a), (b)
In the dust removal card holder of the printer shown in FIG. 1, the card holder surface of the medium position detection sensor mounting portion is formed in a U-shaped (or U, V-shaped or the like) convex shape opened to the medium suction side.

The card holder 1 is fixed to the print head 2 by a fixing member (not shown) so that the card holder 1 moves at the same time as the print head 2. Further, the medium position detection sensors 5 for detecting the front, rear, left and right positions of the medium to be printed are mounted in at least one or more of the two sensor holes 4 at both ends of the card holder 1. At this time, the positional relationship between the sensor surface 9 and the card holder lower surface 1a is as follows.
The convex surface around the medium position detection sensor 5 is set so as to be substantially flush with the medium conveyance direction 8 when the medium conveyance direction 8 is set to the direction in which the medium is conveyed from the front to the rear with respect to the card holder 1.
The U-shaped convex surface 3 is open only at the front. Note that the convex shape need not be limited to a U-shape as long as the front in the transport direction 8 is open, and may be a U-shape or a V-shape. By doing so, the sensor surface 9 of the medium position detection sensor 5 is used when the medium 6 is conveyed from the conveyance direction 8 and enters the card holder 1 and when the card holder 1 moves in the spacing direction 11 during printing. In addition, since the sensor 5 is not damaged by the front and rear ends and the left and right ends of the medium 6 and the medium surface immediately after printing does not contact the sensor 5, there is no contamination due to ink transfer. Also,
The U-shaped convex surface 3 around the sensor hole 4 is spaced apart from the sensor hole 4 by a distance a to the left and right, respectively, in the front-rear direction, by a distance b toward the back, and formed from a position in front of the distance c by the distance c. I do.

FIG. 2 is a side sectional view for explaining the operation of the present invention. The medium 6 is the U-shaped convex surface 3 of the card holder 1
, An airflow 7 in the direction indicated by the arrow is generated.
That is, the airflow 7 is constantly generated around the medium position detection sensor 5 as the medium 6 passes, so that paper dust and dust do not accumulate on the sensor surface 9. Further, since the left and right and front and rear directions from the sensor hole 4 to the convex surface 3 are separated by the distances a and b, an air current is always generated even by the spacing operation during printing, and dust adheres and accumulates on the sensor surface 9. Will not be.

[0050]

According to the dust removing card holder of the printer of the present invention, since the shape of the card holder is formed as a U-shaped convex surface opened to the medium suction side, dust such as paper dust can be applied to the medium position detecting sensor. Since the adhesion and the accumulation can be prevented, an operation such as sensor cleaning is not required. Further, there is an effect that it is not necessary to add a dust removing mechanism using a plurality of components.

[Brief description of the drawings]

1 (a) and 1 (b) are a front view and a bottom view showing one embodiment of the present invention.

FIG. 2 is a side sectional view for explaining the operation of the present invention.

3A to 3C are perspective views showing a first conventional example,
It is a sectional view and a side view.

FIGS. 4A and 4B are a top view and a plan view showing a second conventional example.

FIGS. 5A and 5B are a bottom view and a side view showing a third conventional example.

6 (a) and 6 (b) are side views showing the use state of FIG. 6;

FIGS. 7A and 7B are a side view and a partial perspective view showing a fourth conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Card holder 2 Print head 4 Sensor hole 5 Medium position detection sensor 6 Medium 7 Air flow 8 Transport direction 9 Sensor surface 11 Spacing direction

Claims (7)

[Claims] 1. A printer having a sensor for detecting a position of the print medium, wherein the print medium is pressed by a card holder and printing is performed by a printer head and a platen, and the print medium side surface of the card holder is provided. A dust removal card holder for a printer, wherein a protrusion is provided near a detection hole of a sensor. 2. The dust removal card holder for a printer according to claim 1, wherein said protrusion has a U-shape. 3. The dust removal card holder for a printer according to claim 1, wherein said projection is V-shaped. 4. The dust removal card holder for a printer according to claim 1, wherein said projection is U-shaped. 5. The dust removal card holder for a printer according to claim 1, wherein the opening of the U-shaped projection is arranged in a direction in which the print medium enters. 6. The dust removal card holder for a printer according to claim 1, wherein an opening of the V-shaped protrusion is arranged in a direction in which the print medium enters. 7. The dust removal card holder for a printer according to claim 1, wherein an opening of the U-shaped protrusion is arranged in a direction in which the print medium enters.