JPS5978880A - Thermal printer - Google Patents

Abstract

PURPOSE:To obtain a thermal printer without causing any wasteness even when a printing ribbon and a carrier are separatedly set by using a system in which the number of characters to be printed on one line is set up, and printing is made after the sending amount of the characters from the usable region of the printing ribbon is determined. CONSTITUTION:Input data are converted into printing patterns, a printing length corresponding to the number of characters is calculated, and a printing ribbon 53 in an amount necessary for the printing of the line is sent in. The start-up position of printing for the carrier 20 is determined, the present usable region of the ribbon 53 and the present position of the carrier 20 are memorized in RAM 95 for the next printing after the ending of the printing of the line, and then the carrier 20 is returned. To send the printing ribbon 53 in necessary amount for the printing, control is made on the rotational number of a drive motor 38 for with drawing the ribbon.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a thermal printer, and in particular to a printing ribbon coated with heat-melting ink on the surface of a recording medium so as not to move relative to the recording medium. arrangement,
The present invention relates to a printing method using a thermal printer in which a thermal head equipped with a plurality of heat generating elements is run to transfer heat-melting ink.

[Technical background and problems]

Traditionally, thermal printers started out using thermal paper as a recording medium, but using thermal paper limits the recording media, so it is now possible to print on plain paper as well. Therefore, a technology has been developed in which a printing ribbon coated with heat-melting ink is used, and the heat-melting ink is melted by a heat-generating element of a thermal head and transferred onto a recording medium. In the case of this method, there is a condition that there should be no relative movement between the recording medium and the printing ribbon during printing. For this reason, the carrier that holds the thermal head is equipped with a mechanism for supplying the printing ribbon and a mechanism for winding it up, and the printing ribbon is bonded to the recording medium via a roller, and the printing ribbon is in contact with the recording medium when the carrier moves. Some printers feed the ribbon in the opposite direction relative to the thermal head, thereby eliminating relative movement between the recording medium and the printing ribbon. This type of printer has the problem that it has many parts mounted on the carrier and is heavy, which hinders high-speed printing. In addition, printing can only be performed when the carrier moves in one direction, and movement in the other direction can only be used for returning, resulting in a low percentage of effective printing time and low efficiency. . For this reason, it is conceivable to dispose the printing ribbon separately from the carrier and send out the printing ribbon for each row of printing, but this method has the problem of a large amount of printing ribbon being wasted.

[Purpose of the invention]

The present invention provides a printing ribbon separate from the carrier to reduce the weight of the carrier, and allows printing to be performed while the carrier moves back and forth in both directions, thereby increasing printing speed. This prevents ribbons from being wasted.

[Embodiments of the invention]

First, the printer main body (1) is constructed by attaching various parts to a main body frame (2). This main body frame (2) has side surfaces (3) facing each other at a predetermined interval.
), and the front side has a ribbon cassette mounting surface (4) extending between these side surfaces (3). Said side (
3) A flat printing platen (5) is suspended and fixed between them, and behind this platen (5) is a round paper feeding platen (6) that constitutes the recording medium feeding mechanism. is held rotatably. This round platen for paper feeding (6
) is a pinch roller (7) held by an arm (not shown) and pressed against the paper feeding round platen (6).
is provided. A paper feed 9 drive platen gear (8) is fixed to the left end of the paper feed round platen (6), and a paper feed drive platen gear (8) is attached to the outer surface of the side surface (3). The paper feed drive gear α1 of the paper feed motor (9) is engaged. In addition, above the rear part of the side surface (3), a paper guide plate attached shirt) Q sword is passed and fixed, and this paper guide plate attached shirt) (
11) is attached with a paper guide plate 03 for feeding the paper α2 as a recording medium between the platen (5) and the pinch roller (7).

Next, the side surface (
3) Between the main carrier shaft α4 and the platen (5)
) is installed parallel to the This main carrier shaft α
Both end portions of 4 are support shaft portions (to) protruding from the side surface (3), and this support shaft portion αQ has a lever-shaped carrier rotation driving rotating member 06, which will be described later, for rotating the carrier. Each is provided. These rotating members 06 for rotating the carrier are urged by a thermal head pullback spring αη in a direction to move the thermal head, which will be described later, away from the platen (5).

Further, a movable carrier shaft guide groove α ladder is formed on the side surface (3), and this movable carrier shaft guide groove Qe
is passed through and both ends are connected to the rotating member α for rotating the carrier.
A movable carrier shaft A fixed to Q is provided. A carrier rod is attached to the movable carrier shaft (to) and the main carrier shaft α→ so as to be slidable left and right. A thermal head (A) is provided at the center of the upper surface of this carrier plane, facing the platen (5) via a heat radiator Q2. On both sides of this thermal head (A), ribbon pressure rollers (C) having a height greater than the width of the printing ribbon (described later) are rotatably provided.
A pair of ribbon feeding rollers (C) are rotatably attached to the front side of these ribbon pressure contact rollers (C).

Further, a carrier drive motor (C) is fixed to the lower right side of the ribbon cassette mounting surface (4) with a screw (C), and a carrier drive wire (B) is wound around this carrier drive motor (C). A carrier drive pulley (c) is formed.・Then, the ribbon cassette mounting surface (4
) Four wire guide rollers are rotatably attached to the lower surface of the ribbon cassette mounting surface (
4) located at both ends. The carrier drive wire (A), which is wound several times around the carrier drive pulley (C), is changed direction by the wire guide roller wire, and its end is fixed to the carrier wire by a wire fixing screw (Co., Ltd.). There is.

Further, a carrier rotation drive shaft guide groove 0 → is formed in the side surface (3), and the carrier rotation drive shaft guide groove 0 is passed through and both ends are fixed to the carrier rotation drive rotation member αQ. Carrier rotation drive shaft 0
2 is provided. A solenoid 01 is attached to the lower center surface of the ribbon cassette attachment surface (4), and the solenoid drive shaft of the solenoid 03 is connected to approximately the center of the carrier rotating member α0.

Further, a print start position setting switch (c) for setting the home position of the carrier wire is provided on the inner surface of the left side surface (3). Further, elongated cassette fixing holes (b) are formed at both ends of the ribbon cassette mounting surface (4). Further, a photointerabutter 0 as a photoelectric detector is mounted slightly to the left of the center of the ribbon cassette mounting surface (4) so as to protrude upward.

A ribbon retraction drive motor 0→ is mounted between the solenoid 03 and the carrier drive motor (c) on the lower surface of the ribbon cassette mounting surface (4) with screws 0→. A ribbon retraction drive pulley (41) is rotatably attached to the right side of the ribbon retraction drive motor 0→.
The upper part of the ribbon cassette mounting surface (4) is a coupling αη, which is a ribbon retraction drive shaft and has a cross-shaped recess that protrudes above the ribbon cassette mounting surface (4). Further, a ribbon winding drive pulley (6) is provided on the left side of the ribbon retraction drive mode 26.
) projects upward from the ribbon cassette mounting surface (4) and serves as a ribbon winding drive shaft (g). A rotation guide shaft O4 is rotatably mounted at a position a predetermined distance to the left of the ribbon winding drive shaft θ1. Therefore, the timing belt drive shaft of the ribbon retraction drive motor (c)) and the ribbon retraction drive pulley 0
A timing belt (g) is wound around the ribbon winding drive pulley (6) and the ribbon winding drive pulley (6). The outer surface of the ribbon take-up drive pulley (6) is polished smooth and is set so that the timing belt θ will slip when the load becomes large.

Next, a ribbon cassette Oη is provided which is attached to the ribbon cassette attachment surface (4). This ribbon cassette &'6 is different from the cassette body O→ and the cassette lid θ. Two cassette set heavy wheels that engage with the cassette fixing holes (b) are formed on the cassette body @→, and a cassette support protrusion (2) that partially protrudes is formed on the lower surface. There is.

A ribbon storage section is formed at the center of the cassette body 0. This ribbon storage section (
A winding shaft for winding and holding an unused printing ribbon ring in a roll is installed on the left side, and a winding shaft for winding up used printing ribbon haze is installed on the right side. ing. These winding shafts (goods) and take-up shafts are provided with the rotation guide shaft @
Fitting holes t4 are formed to be fixedly fitted in the rotating direction of the ribbon winding drive shaft and the ribbon winding drive shaft, respectively.

Next, on the left side of the ribbon storage section, guides for guiding the printing ribbon between the supporting wall on the front side are provided at intervals, and a bottom surface between the guides is provided. An insertion hole (2) for a photointerrupter (Of) is formed in the hole (2). A ribbon guide roller 0◇ is rotatably attached to the end of the guide, and a curved guide branch is formed between the ribbon guide roller 11) and the ribbon outlet. A ribbon guide roller is formed at the ribbon exit, and a tension leaf spring (2) elastically clamps the printing ribbon (to) between the guide branch and provides running resistance. It is provided. Further, a ribbon guide member (2) having a channel-shaped cross section is fixedly attached at at least two points to the outer surface of the rear support wall (2) of the cassette body (B).

This ribbon guide member may be integrally molded with the cassette body at the same time, but in this case, twisting, bending, curving, etc. are likely to occur in the guide portion. Therefore, by forming the ribbon as a separate member and attaching it, twisting and the like will not occur and linearity of the ribbon traveling can be obtained. Two cutouts (2) are formed on the left side of the ribbon guide member along with the support wall. A guide member consisting of two pairs of continuous strips is formed parallel to these cutouts, and
A ribbon extrusion member (c) whose central portion has a connecting portion (7) is provided so as to be guided by the guide member and protrude from the support wall.

Next, a ribbon inlet (2) is opened at the right end of the ribbon guide member (2), and a ribbon guide roller (C) is rotatably attached to this ribbon inlet (2).

Guides 174 for guiding the printing ribbon are formed facing each other between the ribbon guide roller (c) and the ribbon storage section. A tension plate spring 17 to be connected to the printing ribbon brocade is provided immediately before the guide cage ◆. However, the guide Q
A ribbon retracting drive roller 94 is rotatably attached to one of the middle parts of the ribbon retracting drive roller &f), and a fitting protrusion 0'7) that fits with the coupling 0η is formed at the lower end of the ribbon retracting drive roller &f). ing. An auxiliary roller f sand is provided facing such a ribbon drawing drive roller fQ.

This auxiliary roller (c) is a block-shaped support member 0'I that reciprocates in a direction perpendicular to the running direction of the printing ribbon.
The support member f0 is held rotatably in the direction of the ribbon drawing drive roller fO by a pressure spring member integrated with the tension leaf spring fI19.

A plurality of protrusions 8◇ are formed on the lower surface of the cassette lid 4, and these protrusions 6ρ are inserted into cassette lid fixing holes formed in the cassette body. A ribbon replacement lid (2) having a finger hook (2) is attached to the upper part corresponding to the ribbon storage section so as to be openable and closable. Further, a knob guide groove (C) is formed at the upper part of the ribbon extrusion member (C). Above the knob guide groove (c) of the cassette lid, a ribbon holding member (b) having an elongated hole (2) matching the shape of the knob guide groove (2) is provided. This ribbon holding member (2) has its front side fixed to the cassette lid (2), is curved at the middle part, and its tip is raised upwards, and the ribbon holding member (2) is attached to the tip of the ribbon holding member (2). Two ribbon holding tongues (to) located slightly outside the width of the ribbon are bent. Next, a knob is provided which penetrates the knob guide groove (■) and the long hole (■) and is located on the upper surface of the ribbon holding member (B) so as to be slidable back and forth. A holding part (a) that holds the connecting part qO of the ribbon extrusion member (c)
is formed. Further, a guide member 4)]) for guiding the upper edge of the ribbon extrusion member f is integrally formed on the lower surface of the cassette lid θ. These guide members 0〃 have the same shape as the guide members formed on the cassette body 0→.

Next, the electrical control circuit is constructed as shown in FIG. First, print information or function operation (
) is provided in the host device that sends information such as paper feed, etc.), a data latch circuit branch is connected to this host device, and 0PU (c) is connected to this data latch circuit.
is connected. This 0PU (Foundation) has a RAM as a storage unit that temporarily stores information such as the number of characters to be printed on the next line and the usable area of the printing ribbon in the stretched area.
(To) is connected, and the print start position setting switch 0
, ribbon feed switch (to), paper feed switch),
Photointerabutton 0no is connected. The ribbon feed switch (9) does not move the printing ribbon (
While the paper feed switch is pressed, the paper feed α2 is fed out. Furthermore, the photointerchanger 0η is used to detect the presence or absence of a printing ribbon, but when a signal indicating that there is no printing ribbon is output, the 0η
The error indicator (a) connected to the PU (incorporated) via the driver circuit II operates. At the same time, the CPU- cancels the printing operation. The CPU 04 is also connected to four data latch circuits (100) via a data bus (100).
101) (102) (103) (104) and driver circuits (105) (106) (107) (108) are connected to each other. Feeding mop (9)
, the thermal head (a) is connected.

Furthermore, the 0PU (foundation) has a driver circuit (109)
The solenoid 03 is connected through the solenoid 03.

In such a configuration, the basic method of printing operation will be explained first. The printing ribbon (here) is a film base coated with heat-melting ink on one side, and the printing ribbon (hereinafter) is stretched along the paper α so that it does not move relative to the paper α. The thermal head (a) is moved while being connected, and as the head moves, electricity is intermittently applied to the plurality of heating elements to generate heat locally, thereby melting the heat-fusible ink. Paper α
The image is then transferred onto the paper 02 and then visualized by peeling off the printing ribbon from the paper 02. When adopting such a printing method, the printing ribbon (to) is pressed against the paper a2 by the thermal head (a), and even if the thermal head (c) moves, the printing ribbon (to) will not touch the paper a2. It is necessary that no relative movement occurs between the paper a2 and the printing ribbon ring, and that the printing ribbon ring be peeled off from the paper a2 immediately after the ink is transferred by thermal melting. The printing ribbon is a one-time ribbon, and the part used for printing cannot be reused. Therefore, it is necessary to scan the thermal head (a) and then unwind the printing ribbon (to) to ensure that there is no used part in the area to be printed.

Next, the operation of each part will be explained.

First, the paper 02 is inserted by rotating the paper feeding round platen (6) by driving the paper feeding 9 motor (9). A) is automatically fed to the front of the platen (5). At this time, since the solenoid 0 is not energized, the rotating member αQ for carrier rotation driving is in a state of being pulled by the thermal head pullback spring αη, and the carrier wing is connected to the main carrier shaft when viewed from the right. It rotates counterclockwise around α4, and the thermal head (C) is separated from the platen (5). Therefore, the paper α can be inserted without any hindrance. Once inserted, the paper α■ is fed in rows during the printing operation by the rotation of the paper feeding round platen (6) based on the drive of the paper feeding P motor (9).

Next, the movement of the carrier wire, that is, the movement of the thermal head (A), is achieved by rotating the carrier drive motor (C), which rotates the carrier drive wire (B), which causes the carrier (A) to move. It moves along the main carrier shaft Q4 and the moving carrier shaft OI.

The carrier drive motor (c) is capable of forward and reverse rotation, and the thermal head can be moved an arbitrary length in either direction while being accurately synchronized.

Also, when printing starts, the carrier (A) is automatically fed to the left edge, presses the print start position setting switch (C) to set the reference position, moves from this reference position to the right by a predetermined distance, and starts printing. Set the position. This is set by applying a predetermined number of pulses to a carrier drive motor (c) consisting of a pulse motor.

Also, for the carrier wire that moves as described above,
To enter the printing state, the solenoid 01 is energized. As a result, the carrier rotation drive rotating member 06 rotates clockwise when viewed from the right via the solenoid drive shaft (B) and the carrier rotation drive shaft 0, and the moving carrier shaft moves to the α position. is changed and the thermal head (a) is attached to the platen (
5) Force to the side. Of course, since the paper (6) and the printing ribbon exist on the surface of the platen (5), the thermal head (a) is pressed against the printing ribbon. By moving in this state, printing is performed using the method described below.

Next, the installation of the ribbon cassette (L4''I) will be explained. Under normal conditions, the printing ribbon ■ is stretched in a straight line from the ribbon outlet to the ribbon entrance (2), and is guided by the ribbon guide member ■. When setting such a ribbon cassette 0f), the printing ribbon (to) is wound around the ribbon pressure roller (c) as shown in FIGS. 3 and 4. The ribbon must be rotated so that it is positioned in front of the thermal head (C), and the ribbon feed roller (C) must also be wound around it. Next, push out the ribbon cassette @no knob. This state is shown in Figure 6. First, the ribbon cassette in the state shown in Figure 6 (α) is As shown in FIG. 6, the ribbon pressing member (B) is pressed down by the advance of the knob, and the ribbon pressing member (B) is positioned on the outside of the printing ribbon holder.Furthermore, as shown in FIG. When it is pressed, the ribbon extrusion member (c) that is linked to the knob f3 partially extrudes the printing ribbon (to).The extrusion range is limited to the inside of the portion stopped by the ribbon presser tongue (c). After preparing like this, attach the ribbon cassette 0 to the ribbon cassette mounting surface (4).
The position can be determined accurately by fitting the cassette set claw (7) into the cassette fixing hole (G).
As shown in FIG. 7, the printing ribbon trowel is positioned from the inside of the ribbon feeding roller (c) to the outside of the ribbon pressing roller (c) and the thermal head (a). After the ribbon cassette 0η is set, the knob (A) is moved back. As a result, the ribbon pushing member (c) enters inside, and the ribbon pressing member (2) rebounds upward by its own elasticity, releasing the ribbon pressing tongue (c) from the printing ribbon (goods). At this time, some loosening occurs, but it is tightened by feeding the ribbon as described later.

Next, feeding of the printing ribbon will be explained.

The winding shaft around which the unused printing ribbon is wound is fitted into the rotation guide shaft, but is in a freely rotating state.

The take-up shaft for winding the used printing ribbon (g) is fitted into the ribbon take-up 1 drive shaft. Further, the fitting protrusion of the ribbon retraction drive roller rough is connected to the ribbon retraction drive pulley (400 coupling 01). Therefore, when there is a command to feed the printing ribbon, the ribbon retraction drive motor rotates. As a result, the ribbon retraction drive pulley 0Q and the ribbon winding drive pulley (6) receive a driving force via the timing belt 0. At this time, the ribbon retraction drive pulley 0
0 rotates the ribbon retraction drive roller (c) through the coupling 0, which is synchronized with the ribbon retraction drive motor (to), and draws in the printing ribbon.

At the same time, the ribbon take-up drive IJQl is also driven, and the ribbon take-up drive shaft 01 drives the take-up shaft ■ to wind up the drawn-in printing ribbon. In this part, the rotation ratio is set so that even when the winding diameter of the printing ribbon wound around the winding shaft is at its minimum, the ribbon pulling drive roller 171 can pull in a sufficient amount. As the winding diameter increases, the tension between the ribbon pull-in driving roller luff Q increases. However, if tension is generated in this portion, the load will increase and the timing belt (g) will slip between it and the ribbon winding drive pulley (6). Therefore, only the drawn-in printing ribbon can be wound up smoothly.

Next, the relationship between the feed of the printing ribbon and the movement of the thermal head (a) in actual printing will be explained based on FIG. First, in the part labeled printing 1, the code P
The part A to the left of 1 is an unused part, and the part B to the right of Pl is a used part. It is assumed that the thermal head (2) is at the print start position at the left end. Here, if the print command for this line is for 7 characters, the print ribbon (to) is pl-+Q corresponding to 7 characters.
It is sent to the right by the range l. Then, printing for seven characters is performed. The portion marked with an X indicates the printing state in this line. This completes printing one line, and the paper (
In 2), vertical feeding 9 is performed by one line, and the second line of print 2 is ready to be printed. When there is a command indicating that printing of this second line is necessary for 14 characters, the unused portion whose right end was at position P2 is sent to position Q2.

Therefore, the printing ribbon is set so that the left side of Q2 is the unused portion A, and at the same time, the thermal head (A) moves to the right side of Q2 and makes this the starting position.

Then, the thermal head (a) moves from right to left and prints the second line from the opposite direction. In this way, the thermal head (A) returns to the left end printing start position. Furthermore, when printing the third line of Print 3, if 7 characters are to be printed with a space of 5 characters from the left side, the right end P3 of the unused part along with the line feed mark of paper (B)
Transmission for 12 characters is performed so that the character reaches the position Q3. Then, the thermal head (A) is moved from left to right, and the third line is printed until it reaches the Q3 position and the right side. Next, in the fourth line of printing 4, it is assumed that five characters are printed with a space for two characters on the left side. At this time, since the right end of the unused portion of the print ribbon branch is at position P4, it is only necessary to feed it by two characters to position Q4. Therefore, the printing ribbon (to) is fed by two characters as the paper is fed by one line, and the thermal head is moved from right to left to print the fourth line from the opposite direction. Furthermore, in printing 5, the printing on the 5th line is only two characters, and the right end of the unused part of the printing ribbon (to) is always at position P5, so the line of paper (c) is If you do this, two characters will be printed without having to feed the printing ribbon (pt).

In this way, the thermal head (A) prints in both directions, both when moving from left to right and from right to left.
Furthermore, at this time, the printing ribbon (to) only needs to be fed by the distance corresponding to the number of characters to be printed in the next line, so the amount of wear is reduced.

The work at this time can be summarized as shown in Figure 10. After the power is turned ON and the circuit and software are initialized, when data is input, this data is converted into a printing pattern and the printing length corresponding to the number of characters is calculated. Then, in response to a print start signal, the amount of printing ribbon necessary for printing that line is fed. Next, depending on the position of the carrier handle, a check is made to see if it is OK to print to the right. If it is OK, it is printed to the right, and if not, it is checked to see if it is OK to print to the left. If so, print to the left. If the printing start position for that line cannot be reached unless the carrier feather is moved to the right or left, check whether moving to the right is closer, move it to the right or left to determine the print start position, and then move the carrier feather to the right or left. Or print to the left. After the printing of that line is finished, the current usable area of the printing ribbon and the position of the carrier wire are stored in RAMH for the next printing, and the process returns.

Note that in order to feed the required amount of printing ribbon for printing, it is sufficient to control the rotation speed of the ribbon retraction drive motor (c), but in reality, the ribbon retraction drive motor (c) is a pulse motor. sb, when the shift of one phase corresponds to feeding the tape for n characters, the shift is determined according to the number of characters required.

Note that this type of printing method represents the most preferable example.In order to be able to print from any direction during the reciprocation of the thermal head, a portion of the print ribbon () is attached to the print ribbon regardless of the number of characters to be printed. It is also possible to send the entire range. Also, from another point of view, if the purpose is to reduce the amount of consumption of printing ribbons,
The thermal head (2) prints only in one direction from left to right.

The feed of the print ribbon (on each line) may be controlled as described above in accordance with the number of characters to be printed.

When considering the state in which such printing is performed, by energizing the solenoid 01, the carrier wing rotates and urges the thermal head (a) toward the platen (5). The state shown in Figure 3 is still solenoid 03.
Thermal head (A) is not energized.
is separated from the printing ribbon (to). In this state, even if the carrier wire reciprocates, the print ribbon does not move and only the carrier wire moves. However, when solenoid 01 is energized, not only the thermal head ta but also the ribbon pressure roller (to) moves the print ribbon. (to) is in pressure contact with the paper ←, so even if the thermal head slope moves, there will be no relative movement at all in the relationship between the paper and the printing ribbon (to). Therefore, even if the heating element of the thermal head (A) is energized to heat and melt the ink on the printing ribbon (To), that part does not move, and the printing ribbon (To) is pressed against the paper by the ribbon pressure roller (C). When it is peeled off from α■, the hot melted ink is transferred onto the paper (6) and printed.

Further, the ribbon feeding roller (c) feeds the printing ribbon ring into the groove of the ribbon guide member (2). The base bar of the printing ribbon is made of a material that easily generates static electricity, such as general polyester film, and is attached to the inner wall of the groove between it and the ribbon guide member (2) to generate static electricity. This results in
Twisting and curving are prevented even when the printing ribbon is stretched over a long distance.

Further, as described above, the printing ribbon (G) receives the driving force from the ribbon retracting drive roller H and is fed intermittently. However, the used portion of the printing ribbon is mechanically weakened due to heat exposure and other causes. Therefore, if a sudden tensile force is applied, there is a risk of it breaking, but the strong tensile force is buffered by the presence of the tension leaf spring (c), thereby protecting the printed bonsakaki.

The printing ribbon consumed in this way) has a winding shaft (
The printing ribbon is unraveled from the ribbon and wound onto the take-up shaft, but at both ends of the printing ribbon branch, that is, at the connection between the winding shaft and the take-up shaft, a transparent portion is formed for a predetermined length. exists. Under normal conditions, when the ribbon cassette zero force is set on the cassette mounting surface (4), the cassette mounting surface (4)
The photointerabutment attached to 4) entered the insertion hole of the ribbon cassette 0″I) and entered inside it.
They are located on both sides of the printing ribbon Q as shown in FIG. At this time, if the printing ribbon is present, the light between the light emitting part and the light receiving part is blocked, thereby making it possible to confirm that the printing ribbon is in the ribbon cassette. Therefore, it is no longer necessary to forget to set the printing ribbon before starting the operation.

Further, when the printing ribbon Q ends and the transparent portion at the end reaches the position of the 7th interrupter 0, a photoelectric detection signal is generated, thereby generating a signal indicating that the printing ribbon Q has ended.

When the printing ribbon (3) is finished in this way, it is a one-time ribbon and must be replaced with a new one. When replacing it, attach the ribbon storage compartment) @7) to the main body frame (2) and remove the ribbon replacement lid (9).
wealth). Then, use the tip of the new printing ribbon (to) that has been wound into a roll to use the used printing ribbon (to).
Connect it to the terminal end of the winding shaft and set it at the winding shaft (goods) position. At this time, the used part of the winding shaft with a large diameter is removed. After doing this, the ribbon retraction drive motor (b) is driven to feed the printing ribbon (to). As a result, the new printing ribbon passes through the front of the thermal head (A), and its leading end is fed into the ribbon storage section (A). And the printing ribbon (to)
Separate the tip from the end of the used printing ribbon (goods), discard the used one, and replace it with a new printing ribbon.
The tip of the winding shaft is connected to the winding shaft. Therefore, the printing ribbon can be easily replaced without removing the ribbon cassette @71.

〔Effect of the invention〕

The present invention sets the number of characters to be printed on a line before printing by the thermal head as described above, and also determines the sender from the usable area of the print ribbon. There is no waste even if the ribbon is installed separately, and the printing ribbon can be used effectively as a one-time ribbon. In particular, since the printing ribbon is stored in the ribbon cassette, it is easy to set it in the printer This is extremely easy, and the printing ribbon is also fed by connecting the ribbon retraction drive motor provided in the printer body via the ribbon retraction drive shaft and ribbon retraction roller.
Even if a ribbon force setter (1) is provided as a separate member, the printing ribbon can be easily fed, and the feeding amount can be reliably set by controlling the rotation speed of the ribbon retraction drive motor. .

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is an exploded perspective view, FIG. 2 is a plan view with the cassette lid removed, FIG. 3 is a plan view of the carrier portion, and FIG. 4 is a plan view of the carrier portion. Fig. 5 is a plan view of a part of the photointerabutment part, Fig. 6 (α) (7) (Gl shows the state of the ribbon cassette when the knob is operated). 7 is a horizontal sectional plan view of a state corresponding to FIG. 6 (C1), and FIG. 8 is an explanatory diagram showing the relationship between the feeding of the printing ribbon and the movement of the thermal head for printing. , FIG. 9 is a block diagram, and FIG. 10 is a flowchart. 1... Printer main body, 4... Number of ribbon cassettes, 20... Carrier, 22... Thermal head, 3
8... Ribbon retraction drive motor, 41... Coupling (ribbon retraction drive shaft), 47... Ribbon cassette, 53... Printing ribbon, 54... Winding shaft, 5
5... Winding shaft, 76... Ribbon retraction drive roller, 95... RAM (memory unit) Applicant Tokyo Electric Co., Ltd.

Claims (1)

[Claims] A ribbon cassette mounting surface is formed on the printer body in which a carrier holding the thermal head is provided so as to be able to freely move back and forth.
A ribbon retraction drive shaft connected to a ribbon retraction drive motor is provided on the ribbon cassette mounting surface, and a winding shaft and a winding shaft for winding and holding the printing ribbon coated with heat-melting ink are provided, and the ribbon A ribbon cassette is provided, the ribbon cassette being removably attached to the ribbon cassette mounting surface, the ribbon cassette having a ribbon retraction drive roller connected to a retraction drive shaft to feed the printing ribbon in one direction, A storage unit is provided for storing the number of characters to be printed and the usable area of the printing ribbon, and the number of rotations of the ribbon retraction drive motor is controlled based on a signal from the storage unit to correspond to the number of characters to be printed. A thermal printer characterized in that the printing ribbon is fed out within a usable range.