JP2001301295A - Method for detecting residual quantity of ink in ink ribbon - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for detecting the residual quantity of ink in an ink ribbon so that print operation can be effected up to the lowest printable limit of residual quantity of ink. SOLUTION: A reflective member 19 is provided in a ribbon cassette at a position facing a detection member 18 through an ink ribbon 17 when a ribbon cassette 16 is mounted on a carriage 7. Light emitted from a light emitting element (not shown) of the detection member 18 transmits the ink ribbon 17 and reflects on the reflective member 19. A light receiving element (not shown) of the detection member 18 detects the quantity of the reflected light transmitted the ink ribbon 17 again. Since the light receiving element detects variation in the quantity of transmitted light thus detecting the residual quantity of ink in the ink ribbon 17, the residual quantity of ink can be detected during print operation or during rewind operation of the ink ribbon.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for detecting the remaining amount of ink on an ink ribbon, which is capable of detecting the remaining amount of ink on an ink ribbon that can be used for printing the same portion a plurality of times.

[0002]

2. Description of the Related Art Conventionally, a recording medium and an ink ribbon have been supported in front of a platen, and a thermal head having a plurality of heating elements is reciprocated along a platen together with a carriage, while a heating element of the thermal head is moved. By selectively generating heat based on print information, a thermal transfer printer that transfers the ink of the ink ribbon to a recording medium and prints an image such as a desired character or graphic on the recording medium has high print quality and low print quality. Due to noise, low cost, ease of maintenance, and the like, they are often used as output devices for computers and word processors.

[0003] The ink ribbon used in such a thermal transfer printer is a one-time ribbon that cannot be used again after one-time winding is completed and printing is completed. For this reason, there has been a problem that the consumption amount of the ink ribbon increases and the running cost increases. In addition, the number of replacements of the ribbon cassette is increased, and the replacement operation is troublesome. Therefore, as one of the methods for reducing the running cost of the ink ribbon, a multi-time ribbon capable of providing the same portion for printing a plurality of times has been proposed. Printing can be repeated multiple times with a ribbon, and running costs can be reduced.

In the ink ribbon composed of such a multi-time ribbon, when the same portion is repeatedly subjected to printing, the ink film thickness is reduced, the remaining ink amount is reduced, and when the ink film thickness becomes smaller than a predetermined value. As a result, print quality for printing on a recording medium is reduced. Therefore, when printing with a ribbon cassette containing an ink ribbon composed of a conventional multi-time ribbon by using a thermal transfer printer, the number of times the ink ribbon is wound in one direction or the number of times the ink ribbon is rewound in the other direction. Was counted by a control unit (not shown), and when this number reached a predetermined number, the ribbon cassette was replaced with a new one. For example, when the number of rewinds counted by the control unit reaches 10, printing is temporarily stopped, the end of use of the ribbon cassette is notified to the operator, and the operator replaces the ribbon cassette with a new one.

[0005]

However, in the conventional method as described above, even if the remaining amount of ink on the ink ribbon is still small enough to be used for printing, the number of times of rewinding of the ink ribbon counted by the control unit is counted. When the number of times has reached the predetermined number, the ribbon has been replaced with a new one, and the ink ribbon has been wasted. On the other hand, even if the remaining amount of ink on the ink ribbon is not enough to be used for printing,
Since the printing is continuously performed until the number of rewinds of the ink ribbon counted by the control unit reaches a predetermined number, there is a problem that the print quality of an image printed on a recording medium is reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and it is possible to detect the remaining amount of ink in an ink ribbon and print the minimum amount of ink that can be used for printing. It is an object of the present invention to provide a method for detecting the remaining ink amount of an ink ribbon.

[0007]

According to a first aspect of the present invention, there is provided a method for detecting the remaining amount of ink on an ink ribbon, comprising the steps of: And a carriage on which the ribbon cassette can be placed.
A detection member capable of detecting the ink remaining amount of the ink ribbon reduced by performing the same portion for a plurality of times of printing is provided, and the detection member detects the ink remaining amount of the ink ribbon. To replace the ribbon cassette.

As a second means for solving the above problem, the detecting member has a light emitting element and a light receiving element, and a light amount when light from the light emitting element passes through the ink ribbon. The change is detected by the light receiving element, and the remaining amount of ink in the ink ribbon is detected.

As a third means for solving the above-mentioned problem, when the ribbon cassette is mounted on the carriage, the light emission is provided on the back side of the ink ribbon opposite to the surface on which the ink is applied. A reflecting member capable of reflecting light from the element is provided, and the light from the light emitting element transmits through the ink ribbon and is reflected by the reflecting member, and the reflected light changes the amount of transmitted light transmitted through the ink ribo again. The method was such that the light receiving element detected.

According to a fourth aspect of the present invention, when the ribbon cassette is mounted on the carriage, the reflection member is provided on the ribbon cassette positioned on the back side of the ink ribbon. The method was formed on a part or a part of the carriage.

According to a fifth aspect of the present invention, an output voltage of the detection member changes in response to a change in the amount of light transmitted through the ink ribbon. The method is such that the remaining amount of ink in the ink ribbon is detected.

According to a sixth aspect of the present invention, the detecting member has a light emitting element and a light receiving element, and light from the light emitting element is provided at a head and an end of the ink ribbon. A method is provided in which a reflective marker is formed, and the leading and trailing ends of the ink ribbon can be detected by detecting the marker with the detecting member.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for detecting the remaining ink amount of an ink ribbon according to the present invention will be described below with reference to FIGS. First, FIG. 1 is a perspective view of a thermal transfer printer according to the present invention, FIG. 2 is a top view of a main part for explaining a method of detecting the remaining ink amount of the present invention, and FIG. 6 is a graph showing a relationship with an output voltage of the first embodiment.

First, as shown in FIG. 1, a thermal transfer printer using the ink ribbon remaining ink amount detecting method of the present invention has a casing 1 made of a metal plate or the like disposed on an outer peripheral portion. Side plates 1a and 1b are integrally formed at the left and right ends in the drawing. At a predetermined position of the housing 1, a plate-shaped horizontally long platen 2 is attached. The platen 2 has a printing surface 2a on the surface formed flat by an elastic member such as rubber. Below the platen 2 in the figure, there is provided a paper feed roller 3 made of rotatable rubber or the like, and a pressure contact roller 4 which is in pressure contact with the paper feed roller 3 and which can rotate following the rotation of the paper feed roller 3. Are arranged.

A paper discharge roller 5 is disposed above the platen 2 in the figure so that a printed recording medium (not shown) sent from the platen 2 can be discharged. A paper feeding unit 6 to which an automatic paper feeding device (not shown) on which a plurality of recording media are placed is formed on the back side of the platen 2 in the drawing, and the paper feeding roller 3 The recording medium sent to the platen 2 can be conveyed to the platen 2 side by the paper feed roller 3 and the pressing roller 4.

On the side of the platen 2 facing the printing surface 2a, there is provided a carriage 7 which can reciprocate in the directions of arrows A and B along the longitudinal direction of the platen 2. The carriage 7 is supported by a rod-shaped guide shaft 12, is stretched around a timing belt 14 wound around a drive gear 13, and drives the drive gear 13 to rotate. Can reciprocate in the directions of arrows A and B. In such a carriage 7, a flat cassette mounting surface 7a is formed on the upper surface, and a winding bobbin formed of a rotatable winding bobbin is provided at a predetermined distance from the center of the cassette mounting surface 7a. A member 8 and a rewinding member 9 composed of a supply bobbin are formed to protrude upward.

The take-up member 8 is spline-engageable with a take-up reel 16b of the ribbon cassette 16 described later, and the rewind member 9 is spline-engageable with a supply reel 16c of the ribbon cassette 16 described later. It has become. Then, by rotating the take-up reel 16b shown in FIG. 1 in a counterclockwise direction, an ink ribbon 17 to be described later can be taken up on the take-up reel 16b. , The ink ribbon 17 described later can be rewound to the supply reel 16c.

Further, a thermal head 15 which can be moved toward and away from the platen 2 is attached to the carriage 7 on the side facing the printing surface 2a of the platen 2. The thermal head 15 is formed with a plurality of heating elements (not shown) arranged on the side facing the platen 2 in the vertical direction. The plurality of heating elements can selectively generate heat based on print information. The thermal head 15
Is movable toward and away from the platen 2 by a cam member (not shown) provided inside the carriage 7, that is, the head can be moved up and down.

The carriage 7 has a thermal head 1 on it.
A roller driving member 10 which can be engaged with a ribbon roller 16e of a ribbon cassette 16 described later protrudes from the left corner of the drawing where 5 is located. The roller driving member 10 is rotatable in conjunction with the rotation of the winding member 8.

The cassette mounting surface 7a of the carriage 7
, A ribbon cassette 16 can be mounted. As shown in FIG. 1, the ribbon cassette 16 has a substantially rectangular case 16a forming an outer shell and has a hollow inside. A take-up reel 16b that can be spline-engaged with the take-up member 8 of the carriage 7 and a supply reel 16c that can be spline-engaged with the rewind member 9 are provided in the case 16.
a are rotatably disposed at substantially the center of the a.

The ribbon cassette 16 has a case 16a.
A concave head insertion portion 16d is formed on one end side of the cartridge. When the ribbon cassette 16 is mounted on the carriage 7, the thermal head 15 is positioned at the head insertion portion 16d. A ribbon roller 16e rotatable in contact with an ink ribbon 17 to be described later is provided at the left corner of the head insertion portion 16d in the figure. The ribbon roller 16e is configured such that the roller driving member 10 on the carriage 7 side can be spline-engaged.

A pair of guide rollers 16f which can guide the movement of the ink ribbon 17 during printing in the width direction which is the vertical direction in the drawing is rotatably provided at the front ends of the left and right side walls constituting the head insertion portion 16d. It is arranged. In addition, an ink ribbon 17 having an ink film made of a heat-meltable ink of a predetermined color formed on one surface of a transparent film is accommodated in the hollow of the ribbon cassette 16, and one end of the ink ribbon 17 is wound. The other end is wound around the supply reel 16c around the take-up reel 16b. Then, a part of the ink ribbon 17 is pulled out to the outside from the head insertion part 16d and is exposed.

In the initial state before use, the ink ribbon 17 is wound around a supply reel 16c in a pancake shape and can be wound around a take-up reel 16b. The ink ribbon 17 is formed of a multi-time ribbon that has a thick ink film and can be used for printing the same portion a plurality of times. for that reason,
By using the ink ribbon 17, the same ink ribbon 17 can be repeatedly printed about 5 to 20 times.

When the ribbon cassette 16 is mounted on the carriage 7, as shown in FIG.
On the right side of the thermal head 15 in the drawing, the ribbon cassette 16
A detection member 18 having a light emitting element (not shown) capable of detecting the remaining amount of ink in the ink ribbon 17 and a light receiving element (not shown) is provided outside the printer. When the ribbon cassette 16 is placed on the carriage 7, as shown in FIG. 2, the ribbon cassette 16 is located at a position facing the detection member 18 on the back side facing the surface of the ink ribbon 17 on which the ink is applied. A reflecting member 19 is provided on a part of the side wall 16g. The reflection member 19 is made of a thin member such as an aluminum foil, and is attached to the side wall 16g.

Markers (not shown) capable of reflecting light from light emitting elements (not shown) of the detecting member 18 are provided at the head and the end of the ink ribbon 17, respectively.
By detecting this marker by the detection member 18, the head or the end of the ink ribbon 17 can be detected. Then, during the printing operation, the winding of the ink ribbon 17 to one side by the winding member 8 is completed.
When the detecting member 18 detects the marker at the end of the ink ribbon 17, the printing operation is stopped. Then, the carriage 7 is moved in the direction of arrow A to return to the initial position which is the printing start position. Thereafter, the rewind member 9 is driven to rotate, and the ink ribbon 17 wound on the take-up reel 16b is rotated.
Is rewound on the supply reel 16c. When the detecting member 18 detects the leading marker during the rewinding operation, the rewinding operation is stopped, and printing is repeated with the same ink ribbon 17 again.

A method for detecting the remaining amount of ink on the ink ribbon of the present invention for preventing the remaining amount of ink on the ink ribbon 17 from decreasing due to such repeated printing and deteriorating the print quality will be described. First, the ribbon cassette 16 is mounted on the cassette mounting surface 7a of the carriage 7, and the operation of simultaneously printing one line or a plurality of lines on a recording medium by the thermal head 15 is repeated, and a desired image is printed on one sheet of recording paper. Print.

By repeating such a printing operation,
When the winding of the ink ribbon 17 wound around the paper supply reel 16c onto the take-up reel 16b is completed, the printing operation is temporarily stopped by the detection member 18 detecting the marker at the end of the ink ribbon 17. After the printing operation is stopped, the supply reel 16c is rotated in the direction of arrow C by the rewind member 9, and the ink ribbon 17 wound on the take-up reel 16b is rewound on the supply reel 16c.

When the ink ribbon 17 is rewound, the detecting member 18 is operated to emit a light emitting element (not shown), and the light of this light emitting element passes through the ink film of the ink ribbon 17 being rewound. When the light reaches the reflection member 19, the light transmitted through the ink film is reflected by the reflection member 19 and transmits again through the ink film of the ink ribbon 17. The amount of light transmitted through the ink film changes due to a change in the thickness of the ink film.
That is, when the ink film immediately after the start of using the ink ribbon 17 is thick and the remaining amount of ink is large, the amount of light transmitted through the ink film is small. Further, when the ink film is thinned and the remaining amount of ink is reduced by performing repeated printing, the amount of light transmitted through the ink film increases. The output voltage of the light receiving element changes according to the change in the light amount.

The relationship between the change in the output voltage and the number of times of printing was determined from experimental results. Referring to FIG. 3, the output voltage before starting the first printing when the ink was not consumed at all was 0.5V. However, the output voltage increases as the number of prints increases. Then, when the number of times of printing reached 11, the print quality of the image printed on the recording medium reached an acceptable level. The output voltage of the light receiving element at this time is 3.
It was 5V. By detecting such a change in the output voltage of the detection member 18, the remaining amount of ink on the ink ribbon 17 can be detected with high accuracy, and the ink ribbon 17 can be used without waste.

Since the light reflected from the markers formed at the head and the tail of the ink ribbon 17 does not pass through the ink film, the light amount is large, and the output voltage of the light receiving element is five.
V or so. For this reason, it is possible to distinguish whether the light detected by the detection member 18 is from the reflection member 19 or from the leading and trailing markers. In the description of the embodiment of the present invention, the reflection member 1
Although the description has been made on the assumption that the reference numeral 9 is attached to the ribbon cassette 16, the reflection member 18 may be provided on a part of the carriage 7. Alternatively, the reflection member 19 may be formed on the back side of the ink ribbon 17 on which the ink film is formed. Further, the reflection member 18 may be one coated with white paint or the like instead of the aluminum foil.

[0031]

As described above, in the method for detecting the remaining amount of ink in the ink ribbon of the present invention, the remaining amount of ink in the ink ribbon is detected by the detecting member, and the ribbon cassette is replaced based on the detection result. Therefore, printing can be repeatedly performed until just before the print quality deteriorates, the ink ribbon can be used without waste, and the running cost can be reduced.

Further, since the light receiving element detects a change in the amount of light when the light from the light emitting element passes through the ink ribbon and detects the remaining amount of ink in the ink ribbon, the remaining ink amount can be accurately detected. can do.

The light from the light emitting element passes through the ink ribbon and is reflected by the reflecting member, and the light receiving element detects a change in the amount of transmitted light which is transmitted through the ink ribbon again. Since the remaining amount of ink in the ink ribbon is detected, the remaining amount of ink can be detected during printing or during the operation of rewinding the ink ribbon. Therefore, you do not need to temporarily stop printing,
A highly accurate remaining amount of ink can be detected regardless of the printing speed.

The reflection member is formed on a part of the ribbon cassette located on the back side of the ink ribbon or on a part of the carriage when the ribbon cassette is mounted on the carriage. It is economical without forming a reflection member on the front surface of the back of the ink ribbon.

The output voltage of the detection member changes in accordance with the change in the amount of light transmitted through the ink ribbon, and the remaining amount of ink in the ink ribbon is detected based on the change in the output voltage. The ink remaining amount can be detected with high accuracy.

Further, the detecting member has a light emitting element and a light receiving element, and a marker capable of reflecting light from the light emitting element is formed at a leading end and an end of the ink ribbon. By detecting by the head of the ink ribbon, and the end can be detected,
One detection member can be used for both detection of the remaining amount of ink and detection of the head and end of the ink ribbon. Therefore, a low-cost thermal transfer printer can be provided by using the method for detecting the remaining ink amount of the ink ribbon of the present invention.

[Brief description of the drawings]

FIG. 1 is a perspective view of a thermal transfer printer according to the present invention.

FIG. 2 is a main part top view for explaining a method for detecting the remaining amount of ink according to the present invention.

FIG. 3 is a graph showing the relationship between the number of times of printing and the output voltage of a detection member according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Housing 1a, 1b Side plate 2 Platen 7 Carriage 7a Cassette mounting surface 8 Winding member 8a First gear 9 Rewind member 10 Roller driving member 10a Second gear 10b Elastic member 11 Intermediate gear 15 Thermal head 16 Ribbon cassette 16a Case 16b Take-up reel 16c Supply reel 16d Head insertion part 16e Ribbon roller 16f Guide roller 16g Guide part 16h Ribbon traveling part 17 Ink ribbon 18 Detection member 19 Reflection member

Claims (6)

[Claims] 1. A ribbon cassette containing an ink ribbon composed of a multi-time ribbon capable of printing the same portion a plurality of times, and a carriage on which the ribbon cassette can be mounted. Is provided with a detecting member capable of detecting the remaining ink amount of the ink ribbon reduced by performing the same portion for printing a plurality of times, the detecting member detects the remaining ink amount of the ink ribbon, A method for detecting the remaining amount of ink in an ink ribbon, wherein the ribbon cassette is replaced based on a detection result. 2. The method according to claim 1, wherein the detecting member has a light emitting element and a light receiving element, and the light receiving element detects a change in the amount of light when light from the light emitting element passes through the ink ribbon. 2. The method according to claim 1, wherein the remaining amount of ink is detected. 3. When the ribbon cassette is mounted on the carriage, a reflecting member capable of reflecting light from the light emitting element is provided on a back side of the ink ribbon opposite to a surface on which the ink is applied, and The light from the light emitting element transmits through the ink ribbon and is reflected by the reflective member, and the light receiving element detects a change in the amount of transmitted light that is transmitted through the ink ribbon again. 3. The method according to claim 2, wherein the remaining amount of ink is detected. 4. The method according to claim 1, wherein the reflecting member is formed on a part of the ribbon cassette located on the back side of the ink ribbon or a part of the carriage when the ribbon cassette is mounted on the carriage. Claim 3
A method for detecting the remaining ink amount of the ink ribbon described in the above. 5. An output voltage of said detection member changes in accordance with a change in the amount of light transmitted through said ink ribbon, and the remaining amount of ink in said ink ribbon is detected based on the change in said output voltage. Claims 2 and 3,
Or the method for detecting the remaining amount of ink in the ink ribbon according to 4. 6. The detecting member has a light emitting element and a light receiving element, and a marker capable of reflecting light from the light emitting element is formed at a leading end and an end of the ink ribbon, and the marker is attached to the detecting member. 2. The ink ribbon remaining amount detecting method according to claim 1, wherein the head and the end of the ink ribbon can be detected by detecting the ink remaining amount of the ink ribbon.