JPS62181178A - Ink ribbon cassette - Google Patents

Abstract

PURPOSE:To prevent an ink ribbon from sagging under a head-up condition and prevent rubbing of a recording head and the ink ribbon on each other or contamination from occurring, by providing tension levers so energized as to stretch the ink ribbon substantially symmetrically on left and right sides with respect to a recording head. CONSTITUTION:Left and right tension levers 22, 23 are turned in the directions of arrows until stoppers 22A, 23A thereof comes into contact with each other, the spring forces of torsion coil springs 24, 25 wound around a shaft 21. When a recording head 4 is turned up in the direction of an arrow, the part of an ink ribbon 10 paid out under a head-down condition sags on the front side of the head 4. However, with the take-up of the ink ribbon 10 simultaneously stopped by stopping the movement of a carriage 3 or by stopping a ribbon taking-up motor, the tension on the ribbon on the take-up side is removed, so that the left tension lever 22 is turned counterclockwise by the force of the torsion coil spring 24, whereby the sag of the ribbon is automatically eliminated.

Description

Detailed Description of the Invention [Technical Field] The present invention relates to an ink ribbon cassette used in a recording device such as a printer or a facsimile machine, and in particular to an ink ribbon cassette of a type that obtains an ink ribbon feeding force by the pressing force between a recording head and a sheet. Regarding the set.

[Prior art]

2. Description of the Related Art Recording devices such as printers and facsimile machines include various recording methods, such as an inkjet type, a wire dot type, and a thermal type.

Thermal methods include a thermal transfer method that uses an ordinary sheet and performs transfer recording via an ink ribbon, and a thermal method that uses a heat-sensitive sheet.

Furthermore, in the thermal type, recording is generally performed while the recording head is pressed against the sheet and is slid.

The present invention relates to an ink ribbon cassette used in a recording head of a type such as this thermal transfer type in which the recording head is pressed against a sheet.

A thermal transfer recording device presses a recording head (thermal head) against a sheet (recording medium such as paper or a thin plastic plate) via an ink ribbon, and generates energy from a plurality of electrothermal transducers (heating elements) provided on the recording head. The dot forming means is configured to perform recording by driving the dot forming means based on print data.

FIG. 1 shows a schematic configuration of a thermal transfer recording apparatus.

In FIG. 1, a sheet 2 backed up by a platen roller 1 is recorded on a recording medium 4 mounted on a carriage 3.

The carriage 3 is movably mounted along a guide shaft 5 installed parallel to the platen roller 1, and is connected to a stepping motor 6, a driving pulley 7, a driven pulley 8, and these pulleys and coupled to the carriage 3. It is reciprocated by a drive diameter consisting of the heald 9.

The recording head 4 has a plurality of heating elements (for example, 24 x 2 elements arranged in two vertical rows or 24 resistors arranged in one vertical row), and has a down position where it is pressed against the sheet 2 and a separation position. It is mounted so that it can swing between the amplifier positions.

An ink ribbon 1 is placed on the carriage 3 in front of the recording head 4.
An ink ribbon cassette (11) for supplying 0 is mounted.

During recording, each heating element is driven based on a data signal, and the recording head 4 is moved in a press-contact state to record while feeding out the ink ribbon 10, and the sheet 2 is conveyed at a predetermined pitch in the direction of arrow P. Create a new line.

By the way, in the conventional ink ribbon cassette 11, as shown in FIG. 2, when the carriage 3 stops after recording and the recording head 4 heads up, the ink ribbon 10 that was recording becomes slack in front of the recording head 4. Put it away.

If there is this slack, there is no problem when skipping during recording (when only carriage 3 is moved without recording) or when returning the carriage, but when sheet 2 is ejected and the next sheet 2 is inserted, The leading end collides with the ink ribbon 10, resulting in a paper jam.

Therefore, f! when sheet 2 was ejected! If the winding force for the ink ribbon 10 is obtained by the moving force of the carriage 3, then the extra carriage 3 is moved, and if it is driven by a motor exclusively for winding, the extra motor is driven, as shown in Fig. 3. There is a problem in that an extra operation must be performed to tension the ink ribbon 10 in front of the recording head 4.

In addition, the moment the extra ink ribbon winds up, the ribbon core (reel) in the supply example rotates due to inertia, so even if there is no slack in front of the recording head 4, the cassette ll
There is some sagging inside.

For this reason, when recording is resumed, the load on the feeding force of the ink ribbon 10 increases at the moment when the slack is gradually removed and the ink ribbon 10 becomes tense, and the sheet 2 is not fed normally due to the pressure contact force of the rad 4 to the recording surface. There was a problem that the ink caused a loss of lη.

In order to prevent this ink staining, the ink ribbon 10
The winding must be stopped slowly over time, but this results in a lot of lost time.

In order to avoid the above problem, it is possible to perform head amplification while the carriage 3 is moving, but in that case, a slight misalignment between the ink ribbon IO and the recording head 4 is likely to occur, and the sheet 2 may be contaminated by ink. There was a problem.

〔the purpose〕

It is an object of the present invention to automatically solve the problems of the prior art as described above, and also to buffer the tension at the moment when the ink ribbon becomes tensioned, thereby preventing trouble between the recording head and the ink ribbon. An object of the present invention is to provide an ink ribbon cassette for a recording device that can prevent dirt and stains.

〔overview〕

The present invention provides tension levers that can be independently swung and are biased so as to tension the ink ribbon approximately symmetrically to the left and right with respect to the recording head. This achieves the above objective.

Embodiment] FIG. 4 shows the internal structure of an ink ribbon cassette 11 according to an embodiment of the present invention.

In FIG. 4, the ink ribbon cassette 11 is provided with a pair of rotatable reels 20 and 20 at predetermined positions within the cassette case formed by the case part 13 and the lid part 12, and the ink ribbon 10 wound around one reel is installed. Recording head 4
It is configured so that it passes through the receiving part 15 and is wound onto a reel in the drawer 17.

The carriage 3 is provided with a ribbon drive shaft (not shown) that is rotated in synchronization with the movement of the carriage during recording, and when the cassette is installed, the ribbon is moved to the reel on the winding side of the pair of reels 20. The drive shaft is fitted, and the ink ribbon 10
It is designed to wind up.

As the ink ribbon 10, either a one-time ribbon that can print on the same area only once or a multi-ribbon that can repeatedly print on the same area can be used.

Further, the inside of the ink ribbon 10 is usually set to a predetermined size or more that covers a recording zone for one line.

As shown in FIGS. 4 and 5, the ink ribbon cassette 11 can be mounted on the carriage 3 with its front and back (upper surface, lower surface) and left and right sides reversed, so that it can be used in either state.

First, bearing portions 16.16.17.17 are formed at opposing positions of the case portion 13 and the lid portion 12 to support both ends of the pair of reels 20.20. Case part 13 and lid part 12
The cassette case is mounted substantially symmetrically in the front and back (up and down) and left and right directions.

Furthermore, the cassette case 11 itself, which is composed of the case part 13 and the lid part 12, has a substantially symmetrical shape structure in the front and back as well as in the left and right directions, and the recording head 4 receiving part 15 is formed in the center of the front surface of the cassette case. reel 20.2
The ink ribbon 10 between 0 and 0 is also guided along a vertically and horizontally symmetrical winding path within the cassette case.

Furthermore, in this type of ink ribbon cassette, an ink end detection means is provided to detect whether the remaining amount of the ink ribbon has reached a predetermined amount or less before the ink ribbon 10 is completely unwound. There is.

This ink end detection means includes a film portion having different reflectance over a predetermined length at the end of the ink ribbon 10, and a ribbon end sensor that protrudes at a predetermined position inside the cassette case when the cassette is attached to the carriage 3.
It has a configuration provided in

The end film part of the ink ribbon 10 is formed of, for example, an aluminum foil or a film coated with aluminum and has a different reflectance from the ink application part, and the ribbon end sensor is composed of, for example, a light emitting element and a light receiving element, and detects changes in the surface reflectance of the ink ribbon 10. A sensor that photoelectrically detects is used.

Concave portions 18 and 19 are formed at predetermined positions adjacent to the path of the ink ribbon 10 in the cassette case consisting of the case portion 13 and the lid portion 12 to receive the ribbon end sensor.

One recess 18 opens on the bottom surface of the case section 13, and the other recess 19 opens on the top surface of the lid section 12.These recesses 18 and 19 are connected to the ribbon drive shaft as shown in FIGS. 4 and 5. The ribbon end sensor on the carriage 3 is received in a predetermined position in either position when the ribbon end sensor 1-11 is installed while being reversed from front to back and from side to side.

When the ink ribbon 10 is a multi-ribbon, the end film portions having different reflectances are provided at both ends thereof.

In FIG. 4, ink ribbons are mounted in a cassette case (case part 13 in the illustrated example) at positions that are approximately symmetrical to the left and right with respect to the recording head 4. A pair of tension levers 22 and 23 are attached which are biased to tension the lO substantially symmetrically to the left and right sides of the recording head 4.

The rotating shaft 21 is provided in the case portion 13 near the recording head receiving portion 15 at approximately the center position of the recording head 4, and the left and right tension levers 22 and 23 are torsion levers wound coaxially with the rotating shaft 21. They are biased by coil springs 24 and 25, and appropriate tension is applied to the left tension lever 22 in a counterclockwise direction and the right tension lever 23 in a clockwise direction.

FIG. 6 shows a section through a portion of the lever including the tension lever 22,23.

In FIG. 6, the right lever 23 is fitted onto the shaft 21,
The left lever 22 is fitted into the mounting portion of the right lever 23, and both swing around the rotating shaft 21.

On the left and right tension levers 22, 23, there is a shaft portion 26 for rotatably mounting an ink ribbon guide roller 28, 29 at a position where the ink ribbon 10 is guided.
, 27 are provided.

Next, the movement of the tension levers 22, 23 will be explained with reference to FIGS. 7 to 1θ.

FIG. 7 shows a resting state in which the recording head 4 is in a head-up state, and the ink ribbon 10 is moved by the left and right tension levers 22.
It is guided by guide rollers 28, 29 on 23.

In the state shown in Fig. 7, each of the left and right tension levers 22.2
3 is a torsion coil spring 24 rotated around the shaft 21;
, 25, each stopper 22A, 23
A is rotated in the direction of the arrow until it collides. Therefore, the ink ribbon 10 is tensioned in front of the recording head 4 in order to escape backwards with respect to the sheet 2.

FIG. 8 shows a state in which the recording head 4 is moving from left to right while recording with the head down, and FIG. 9 shows the state at the moment when it starts moving.

Since the ink ribbon 10 is maintained in a tensioned state and suddenly starts to move from a stationary state, at the moment when the ink ribbon 10 starts to move, as shown in FIG. A strong tension is applied.

Since the force of the torsion coil spring 25 is weak compared to this tension, the right tension lever 23 is rotated counterclockwise by the tension of the ink ribbon 10 until its stopper portion 23B comes into contact. This movement weakens and buffers the impact of the tension of the ink ribbon 10 on the recording head 4.

Once it starts moving, the force for feeding out the ink ribbon 10 is small due to inertia, etc., and the spring force of the torsion coil spring 25 becomes larger, and the tension levers 22 and 23 on the left and right side
The state is as shown in Figure 8, and the right tension lever 2
Only 3 is the same as the initial state (FIG. 7).

Since the left tension lever 22 is on the winding side, the winding tension is always acting on the ink ribbon IO, so it is rotated clockwise by the ribbon tension opposing the spring force of the torsion coil spring 24. The maximum rotation angle of this left tensicon lever 22 is the stopper part 2.
This is the position where it contacts 2B.

When starting recording from an initial state where the supply side of the ink ribbon 10 is slack due to an accident, etc., it will start from the state shown in FIG. In this case, at the moment when the supply side of the ink ribbon 10 is fed out and becomes tensioned after starting, the state shown in FIG. 9 is reached, and as explained above, the impact of the tension of the ink ribbon 10 is buffered.

FIG. 10 shows the state at the moment when the RAD 4 is headed up for recording after the end of recording.

In FIG. 10, when the printing head 4 moves its head up in the direction of the arrow, the ink ribbon 10 that was fed out when the head went down becomes slack in front of the printing head 4.

However, if the carriage 3 stops moving or the ribbon take-up remoter stops winding the ink ribbon 10 at the same time, the ribbon tension on the take-up side disappears, so the left tension lever 22 is moved by the spring force of the torsion coil spring 24. It is rotated counterclockwise, the slack is automatically removed, and the initial state as shown in FIG. 7 is obtained.

Therefore, there is no need to make extra movements to remove slack.

Furthermore, if the spring forces of the torsion coil springs 24 and 25 are set to be the same on the left and right sides, as is clear from the above explanation, the movements of the left and right tension levers 22 and 23 can be made symmetrical, and the ribbon cassette 11 can be reversed from front to back or left to right (upside down), it can perform the same function as before it was reversed, and therefore it becomes easy to store multi-ribbons and the like in a cassette and use them repeatedly.

According to the embodiment described above, the tension levers 22 and 23 are provided which rotate independently on the left and right sides of the recording pad 4 in the ribbon cassette 11, and the slack of the ribbon when the head is up is automatically adjusted using a predetermined tension. Since the ink ribbon is configured to remove the slack, there is no need for extra movement to remove the ribbon slack, and by buffering the tension at the moment the ink ribbon becomes taut, it prevents misalignment and dirt between the recording head and the ink ribbon. An ink ribbon cassette that can eliminate the need for ink ribbons has been obtained.

In addition, since the shape structure of the other parts of the ribbon cassette 11 is substantially symmetrical vertically and horizontally, the same effect can be obtained even when used upside down, and the same part can be used repeatedly, making multi-ribbon economical. An ink ribbon cassette that is effective for general use was obtained.

In the illustrated embodiment, the left and right tension levers 22.
23, the rotation shaft 21 is made into one, but this means that if the left and right sides are approximately symmetrical with respect to the recording head 4, each lever 22.
It is also possible to provide separate rotation axes for each 23.

Furthermore, the present invention also relates to the movement of the recording head 4 and the ink ribbon 1.
The present invention can be similarly applied to ink ribbon cassettes of recording apparatuses other than thermal transfer type, as long as the movement of 0 corresponds to l to l.

〔effect〕

As is clear from the above explanation, according to the present invention, it is possible to automatically take up the slack in the ink ribbon when the head is up, and it is also possible to buffer the tension at the moment when the ink ribbon becomes under tension. An ink ribbon cassette for a recording device is provided.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a main part of a recording apparatus suitable for using the ink ribbon cassette according to the present invention, and FIGS. 2 and 3 are schematic partial plan views illustrating the slack state of the ink ribbon of a conventional ink ribbon cassette. , FIG. 4 is an exploded perspective view of an ink ribbon cassette according to an embodiment of the present invention, and FIG.
Figures (A) and (B) are perspective views of the ink ribbon cassette in Figure 4 when it is turned upside down, Figure 6 is a sectional view of the tension lever attachment part in Figure 4, and Figures 7 to 10 are FIG. 5 is a partial plan view showing movement of the left and right tension levers in FIG. 4; 2-・-1---seat, 3-・-・-carriage, 4-
---------1 Recording head, 10 --- Ink ribbon, 11 --- Ribbon cassette, 21 ------
One rotation axis, 22.23--Tension lever, 24
．． 25--Torsion coil spring. Agent Patent Attorney Yasushi OotoFigure 3Figure 5Figure 6

Claims (1)

[Claims] (1) In an ink ribbon cassette of a printing device that obtains an ink ribbon feeding force by the pressing force between the print head and a sheet, the ink ribbon is independently swingable and records the ink ribbon in approximately symmetrical positions with respect to the print head. An ink ribbon cassette that is equipped with tension levers that are biased to tension the head approximately symmetrically to the left and right.