JPH07403B2 - Printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a carriage movable along a platen,
A print head movably mounted on the carriage between a printing position and a non-printing position, and a ribbon detachably mounted on the carriage and capable of printing many times or a ribbon that allows only one printing are housed. The present invention relates to a printing device including a ribbon cassette.

(Prior Art) In a conventional printing apparatus of this type, a ribbon that can be printed multiple times is always wound in only one direction, and a ribbon cassette is wound when the entire amount of the ribbon is wound on a winding spool. There is a method of reversing and re-loading, or a method of reversing the winding direction of the ribbon when the entire amount of the ribbon is wound on one spool.

(Problems to be Solved by the Invention) However, according to these conventional printing apparatuses, there is a problem that the reversing operation of the ribbon cassette becomes very troublesome in the former case, and the reversing mechanism in the latter case. Had the inconvenience of becoming complicated. Furthermore, in a thermal transfer type printing device that performs printing in a state where the thermal head is pressed against the printing paper via the thermal ribbon, if the feeding direction of the thermal ribbon and the moving direction of the printing head are different,
At the pressure contact portion of the thermal head, relative movement occurs between the thermal ribbon and the printing paper, which causes a problem that the printing paper becomes dirty. Further, according to the ribbon feeding mechanism of the latter printing device, since the feeding amount of the ribbon is set for the printing ribbon many times, it is impossible to use the ribbon cassette which accommodates the ribbon which allows only one printing. There were also points.

(Means for Solving Problems) In order to solve each of the problems described above, according to the present invention, a carriage movable along a platen, and a printing position which is placed on the carriage and is in pressure contact with the platen are provided. A printing apparatus comprising a print head movable between a non-printing position separated from a platen, and a ribbon cassette detachably attached to the carriage, wherein printing is performed only when the carriage moves in one direction, A drive gear that is provided on the carriage and is driven to rotate as the carriage moves, and a drive gear that is provided between the drive gear and a first spool shaft that rotates a take-up spool of the ribbon cassette. The rotation of the drive gear is changed to the first spool so that the first spool shaft rotates in the ribbon winding direction with the movement in one direction. When driven by the print head, the first rotation transmission mechanism transmitting to the pool shaft and the print head located at a non-printing position separated from the platen, the first rotation transmission mechanism drives the drive gear to the first spool. The first releasing means for releasing the rotation transmission to the shaft and the second spool shaft for rotating the drive gear and the supply spool of the ribbon cassette are provided between the first releasing means and the second return shaft of the carriage. The second spool shaft rotates in the ribbon rewinding direction, and the rotation amount thereof is smaller than the rotation amount at the time of rotation transmission from the drive gear to the first spool shaft by the first rotation transmission mechanism. , A second rotation transmission mechanism for transmitting the rotation of the drive gear to the second spool shaft, and the rewinding amount of the ribbon becomes smaller than the winding amount of the ribbon printed immediately before by a fixed ratio. As described above, after the rotation transmission by the first rotation transmission mechanism is released and the rotation transmission by the second rotation transmission mechanism is connected, the rotation transmission from the drive gear to the second spool shaft by the second rotation transmission mechanism is performed. Second release means for releasing the second rotation transmission mechanism and the second drive gear driven by the second rotation transmission mechanism.
Is provided between the third releasing means for releasing the rotation transmission of the sheet to the spool shaft and maintaining the released state, the ribbon cassette mounted on the carriage and the third releasing means, and printing is performed a number of times. Actuating means for invalidating the third releasing means when a ribbon cassette storing a possible ribbon is mounted, and validating the third releasing means when mounting a ribbon cassette storing a ribbon which allows only one printing And are provided.

(Operation) Therefore, in the printing apparatus of the present invention
When a ribbon cassette containing a ribbon that allows only one printing is installed, the third releasing means is activated by the operating means, and the rotation transmission from the drive gear to the second spool shaft by the second rotation transmitting mechanism is performed. Release and maintain the released state. Then, when the print head is arranged at the print position in which the print head is in pressure contact with the platen and the carriage moves in one direction, the rotation of the drive gear is changed to the first direction via the first rotation transmission mechanism.
And the take-up spool of the ribbon cassette is rotated in the ribbon take-up direction. When the carriage returns to the opposite direction to the print head and moves to the non-printing position where the print head is separated from the platen,
The rotation transmission of the drive gear from the drive gear to the first spool shaft is released by the release means, and the rotation of the drive gear is not transmitted to either the first spool shaft or the second spool shaft.
Ribbon feeding is stopped. Therefore, a ribbon that allows only one ribbon is always wound only in the winding direction.

On the other hand, when a ribbon cassette containing a ribbon that can be printed many times is mounted on the carriage, the third cassette is operated by the operating means.
The canceling means of is invalidated. When the carriage moves in one direction, the rotation of the drive gear is transmitted to the first spool shaft via the first rotation transmission mechanism, and the ribbon is wound on the take-up spool. Also, when the carriage returns to the opposite direction to the non-printing position where the print head is separated from the platen, the rotation transmission from the drive gear to the first spool shaft by the first releasing means is released. Meanwhile, the rotation of the drive gear is transmitted to the second spool shaft by the second rotation transmission mechanism, and the ribbon is rewound onto the supply spool. At the time of rewinding the ribbon, the second releasing means is operated so that the rewinding amount of the ribbon becomes smaller than the take-up amount of the ribbon at the time of immediately preceding printing by a fixed ratio. Therefore, when using a ribbon that can be printed many times, the next printing operation is started from a position slightly shifted from the printing start position at the time of immediately preceding printing, and both the winding and rewinding operations are repeated. The ribbon is gradually printed while being printed many times.

(Embodiment) An embodiment in which the present invention is embodied in a thermal printer will be described below with reference to the drawings.

As shown in FIGS. 1 and 2, a platen 1 is fixed to a frame (not shown) of the thermal printer, and a paper guide portion 2 and a paper feed roller 3 are arranged below the platen 1. A carriage body 5 is movably supported by left and right shaft support portions 6 on a support shaft 4 extending below the platen 1 and in parallel with the support shaft 4, and a lower surface of a front end portion thereof is supported on a guide member (not shown). A head carriage 7 is rotatably supported on the support shaft 4 between the shaft support portions 6,
A thermal type print head 8 facing the platen 1 is placed on the upper surface thereof.

At the base end of the print head 8, there is formed a projecting piece 11 having an inclined surface 11a which inclines downward from above. Further, a spring 12 for urging the print head 8 in a direction separating from the platen 1 is stretched between the head carriage 7 and the carriage body 5. Further, an engaging protrusion 9 is formed on the head carriage 7 in a protruding manner, and a release lever 10 which is operated and controlled by a control device (not shown) of the thermal printer is arranged below the engaging protrusion 9. The engagement protrusion 9 is always engaged with the upper surface of the release lever 10. When the release lever 10 is arranged in the solid line position in FIG. 2, the print head 8 is arranged and held in the print position in which the print head 8 is pressed against the platen 1 together with the head carriage 7, and the release lever 10 is arranged in the chain line position in FIG. When the printing is performed, the spring force of the spring 12 causes the print head 8 to be arranged at a non-printing position which is separated from the platen 1 to the front.

A drive pulley 13 and an idle pulley 14 which are normally and reversely rotated by a drive motor (not shown) are disposed on the left and right sides of the frame, and an endless toothed drive belt 15 is mounted between the pulleys 13 and 14. Has been done. A part of the drive belt 15 includes a toothed wall 16a and holding walls 16b and 16c of the carriage body 5.
The carriage main body 5, the head carriage 7 and the print head 8 are fixed by being sandwiched between the drive belt 15 and the drive belt 15 with teeth.
It is reciprocated along the platen 1 as it goes around.

As shown in FIGS. 1 and 4, the toothed drive belt
A first spool shaft 18 is provided on the upper left side surface of the carriage main body 5 in front of 15 so as to be rotatable forward and backward, a connecting cylinder 19 is fixed to an upper end thereof, and a first driven gear is provided to a lower end thereof. 20 is mounted so as to be rotatable integrally with the first spool shaft 18. A second spool shaft 21 is rotatably mounted on the upper surface of the carriage body 5 at a right position away from the first spool shaft 18 by a predetermined distance, and a connecting cylinder 22 is fixed to the upper end of the second spool shaft 21. A second driven gear 23 is attached to the lower end of the second spool shaft 21 so as to rotate integrally therewith.

As shown in FIG. 3, a multi-ribbon cassette 25 is removably mounted on the upper surface of the carriage main body 5, and a take-up spool which is fitted into the connecting cylinder 19 of the first spool shaft 18 inside thereof. 26 and a connecting cylinder 22 for the second spool shaft 21.
And a supply spool 27 which is fitted onto the outer circumference of the supply spool 27. A multi-thermal ribbon R capable of printing a large number of times is wound around both the winding and supplying spools 26 and 27, and a part of the multi-thermal ribbon R is opened at the rear side edge of the multi-ribbon cassette 25 and has a pair of left and right ribbon passage ports 28 and 29. And is exposed to the print head 8 side. Reference numeral 30 shown in FIG. 3 is a leaf spring for applying tension.

On the other hand, as shown in FIGS. 1 and 4, on the carriage main body 5 between the first and second spool shafts 18 and 21, a drive gear that constantly meshes with the inner surface of the toothed drive belt 15. A shaft 33 is rotatably supported by the shaft 32. Then, as shown in FIG. 1, the toothed drive belt 15 has an arrow A
When the print head 8 is moved in the printing direction (the direction of arrow B) together with the carriage body 5 while being rotated in the direction, the drive gear 33 is rotated clockwise in the figure. Further, as shown in FIG. 4, when the toothed drive belt 15 is rotated in the direction of arrow D and the carriage main body 5 is returned and moved in the direction of arrow E, the drive gear 33 is rotated counterclockwise in the same figure. It has become so.

A lever 36 as a first releasing means extending along the upper surface of the carriage body 5 is rotated on a fixed shaft 35 projecting on the carriage body 5 between the drive gear 33 and the first spool shaft 18. An engaging portion 37 that engages with the inclined surface 11a of the print head 8 is formed at its rear end, and this lever 36 is attached to the front end in the clockwise direction in FIGS. A spring 38 for biasing is attached. Above the lever 36, the fixed shaft 35 is fitted with a fixed position gear 39 which always meshes with the first driven gear 20, and the first arm portion 40 behind the lever 36 is always meshed with the fixed position gear 39. And a displacement gear 41 facing the drive gear 33 from the rear side.
Is pivoted.

The fixed position gear 39, the displacement gear 41 and the first
The driven gear 20 of FIG. 1 constitutes the first rotation transmission mechanism of this embodiment, and when the print head 8 is located at the print position as shown in FIG. 1, the lever 36 moves clockwise by the action of the spring 38. Displacement gears arranged in a rotating position in
41 is meshed with the drive gear 33, and the rotation of the drive gear 33 is transmitted to the first spool shaft 18 via the displacement gear 41, the fixed position gear 39 and the first driven gear 20, and the first spool shaft
By rotating 18 in the winding direction of the multi-thermal ribbon R (counterclockwise direction in the figure), the multi-ribbon cassette is rotated.
The multi-thermal ribbon R is wound on the winding spool 26 of 25. Further, as shown in FIG. 4, when the print head 8 is located in the non-printing position separated from the platen 1, the lever 36 is arranged in the counterclockwise rotation position against the action of the spring 38. By disengaging the meshing between the displacement gear 41 and the drive gear 33, the operative connection between the drive gear 33 and the first spool shaft 18 is released, and the take-up spool 26 of the multi-ribbon cassette 25 moves in the ribbon winding direction. The rotation of is stopped.

As shown in FIGS. 1 and 5, a large-diameter gear 44 and a small-diameter gear 45 having a smaller number of teeth at a fixed ratio than that of a large-diameter gear 44 integrally rotate on a shaft 43 provided on the front end portion of the lever 36. 1, the large diameter gear 44 is spaced forward from the drive gear 33 when the lever 36 is in the position shown in FIG. 1, and the large diameter gear 44 is large when the lever 36 is in the position shown in FIG.
44 is adapted to mesh with the drive gear 33. Also, the second protruding portion is formed to protrude laterally from the right edge of the front end portion of the lever 36.
An intermediate gear 47, which meshes with the large-diameter gear 44 and faces the second driven gear 23 on the second spool shaft 21, is axially attached to the tip of the arm portion 46, and the lever 36 is shown in FIG. The intermediate gear 47 meshes with the second driven gear 23 when it is in the position shown in FIG.
It is designed to be transmitted to 45.

As shown in FIGS. 1 and 4, a bifurcated rotary arm 48 that extends by sandwiching a large-diameter gear 44 and a small-diameter gear 45 is rotatably supported at the base end on the shaft 43 of the lever 36. A planetary gear 49, which is always meshed with the small-diameter gear 45 and faces the second driven gear 23 from the front, is axially mounted on the intermediate portion of the second driven gear 23, and the planetary gear 49 is attached to the tip end of the planetary gear 49. A spring 50 is urged in the direction to engage with. Further, the front side edge of the second arm portion 46 of the lever 36 is in contact with the lower rear side edge of the rotating arm 48 to regulate the rotational position of the rotating arm 48 relative to the lever 36 in the counterclockwise direction. The protrusion 51 is integrally formed.

Then, the second driven gear 23, the planetary gear 49, the small diameter gear 45 and the large diameter gear 44 constitute a second rotation transmission mechanism of this embodiment, and as shown in FIG. When rotated in the counterclockwise direction, the rotation arm 48 is rotated counterclockwise about the shaft 43 by the action of the spring 50 following the backward movement of the second arm portion 46, and the planetary gear 49 is moved to the first position. It is meshed with the second driven gear 23. In this state, the rotation of the drive gear 33 is such that the large diameter gear 44, the small diameter gear 45, the planetary gear 49 and the second driven gear 23.
Is transmitted to the second spool shaft 21 through the second spool shaft 21, and the second spool shaft 21 rewinds the ribbon R (clockwise direction in the figure).
And the multi-thermal ribbon R is rewound on the supply spool 27.

On the other hand, an annular groove 54 is provided on the upper surface of the small diameter gear 45,
A ring spring 53, which constitutes the second releasing means of this embodiment, is wound and supported by its inner groove surface by its own spring force, and a projection 52 protruding from the upper surface of the small diameter gear 45 at one end thereof.
Is bent. Then, as shown in FIG.
When the second driven gear 23 and the large diameter gear 44 are operatively connected to each other through the intermediate gear 47, the ring spring is integrated with the small diameter gear 45 based on a predetermined rotation speed of the second spool shaft 21 in the winding direction. The protrusion 52 of 53 is moved by a predetermined amount in the counterclockwise direction in the figure. Also, as shown in FIG.
When the driven gear 23 and the small diameter gear 45 of the above are operatively connected,
As the drive gear 33 rotates, the protrusion 52 of the ring spring 53 moves in the clockwise direction in the figure. Further, when the protrusion 52 moves in the clockwise direction, the number of teeth of the small diameter gear 45 is set to be smaller than that of the large diameter gear 44, so that the second spool shaft 21
Is both gears 44, 4 than the predetermined number of rotations in the winding direction.
When rotated in the rewinding direction by a small number of rotations corresponding to the gear ratio of 5, the protrusion 52 engages the rotating arm 48 and resists the action of the spring 50. Rotate to the position of the chain line. Therefore, at this time, the meshing between the planetary gear 49 and the second driven gear 23 is disengaged, and the operative connection between the drive gear 33 and the second spool shaft 21 is released. When the protrusion 52 and the rotating arm 48 are engaged with each other, the large diameter gear 44 is further moved to the fourth position.
When rotated in the clockwise direction in the figure, the spring force of the spring 50 becomes larger than the tightening force of the ring spring 53 with respect to the inner groove surface of the annular groove 54, and the ring spring 53 moves on the inner groove surface of the annular groove 54. The projection 52 is slipped and held at the position indicated by the chain line.

By the way, the carriage main body 5 of the thermal printer in this embodiment accommodates a multi-ribbon cassette 25 accommodating the multi-thermal ribbon R capable of printing a large number of times and a one-time thermal ribbon (not shown) which allows only one printing. One-time ribbon cassette shown in FIG.
61 and 61 are removably attached to each other. Then, as shown in FIG. 3, the entire lower side surface of the multi-ribbon cassette 25 is smooth, but as shown in FIG. An operating projection 62 as an operating means is provided so as to project downward at a position corresponding to the rotating arm 48, and a lower end thereof has an inverted conical shape engageable with the rear side surface of the distal end portion of the rotating arm 48. The cam portion 63 is formed. Therefore, the rotating arm 48 constitutes the third releasing means of this embodiment, and when the one-time ribbon cassette 61 is mounted on the carriage main body 5, the rotating arm 48 is moved by the cam portion 63 of the operating protrusion 62.
Is rotated clockwise against the action of the spring 50 so that the planetary gear 49 is disengaged from the second driven gear 23 and its disengaged state is maintained. In addition,
The other part of the one-time ribbon cassette 61 excluding the actuating protrusions 62 is constructed in substantially the same manner as the multi-ribbon cassette 25.

Next, the operation of the thermal printer configured as described above will be described.

First, the multi-ribbon cassette is mounted on the carriage body 5.
Multi-thermal ribbon R that can be printed many times by mounting 25
The operation of the printing operation by will be described.

Now, when the multi-ribbon cassette 25 is not attached to the carriage body 5, the release lever 10 is arranged at the chain line position as shown in FIG. 2, and the print head 8 moves to the non-print position due to the action of the spring 12. Is held. The lever 36 is arranged at the position shown in FIG. 4 against the action of the spring 38 by the engagement between the inclined surface 11a of the print head 8 and the lever 36. Then, in this state, as shown in FIG. 3, the multi-ribbon cassette 25 is placed on the carriage body 5 and both the winding and supply spools 26, 27 are provided.
Is fitted to the connecting cylinders 19 and 22 of the first and second spool shafts 18 and 21, and part of the multi-thermal ribbon R exposed to the outside of the multi-ribbon cassette 25 is connected to the platen 1 and the print head 8. Multi-ribbon cassette 25 if placed between
Can be mounted on the carriage body 5.

Next, when a character key or the like on a keyboard (not shown) is operated, the release lever 10 is raised to the position shown by the solid line in FIG. Then, it is rotationally arranged at the printing position. Following the rotation of the print head 8, the lever 36 is rotated to the position shown in FIG.
Are meshed with the drive gear 33. At the same time, drive gear 33
From the large driven gear 23, the intermediate gear 47 is meshed with the second driven gear 23, and the planetary gear 49 is separated from the second driven gear 23.

In this state, the control unit operates the print head 8 to transfer characters and the like onto the print paper P via the multi-thermal ribbon R. Subsequently, the toothed drive belt 15 is the first
The carriage main body 5 and the print head 8 are integrally moved in the printing direction B by being rotated a predetermined amount in the direction of arrow A in the figure, and the drive gear 33 is rotated by a predetermined amount in the clockwise direction in FIG. Then, with the rotation of the drive gear 33, the first spool shaft is moved through the displacement gear 41, the fixed position gear 39, and the first driven gear 20.
18 is rotated by a predetermined amount in the ribbon winding direction, the printed multi-thermal ribbon R is wound on the winding spool 26 in the multi-ribbon cassette 25, and the unprinted multi-thermal ribbon R is fed from the supply spool 27. Be done. In this way, when the printing operation for one line is completed, the second
This means that the spool shaft 21 of the multi-thermal ribbon R is rotated by the number of rotations corresponding to the winding amount of the multi-thermal ribbon R, and the rotation at that time is transmitted through the second driven gear 23 and the intermediate gear 47 to the large diameter gear 44.
Be transmitted to. Therefore, the protrusion 52 of the ring spring 53 has a second
The spool shaft 21 is moved in a direction away from the rotating arm 48 based on the number of rotations of the spool shaft 21 and the gear ratio between the second driven gear 23 and the large diameter gear 44.

Then, when a carriage return button (not shown) on the keyboard is operated, the release lever 10 is moved downward and the print head 8 is pivotally arranged at the non-printing position. Then, as the print head 8 rotates, the lever 36 is arranged at the position shown in FIG. 4, and the drive gear 33 and the first spool shaft are
The operative connection with 18 is released. At the same time, the large gear 44 is meshed with the drive gear 33, the intermediate gear 47 is separated from the second driven gear 23, and the second driven gear 23 is separated from the second driven gear 23.
The planet gear 49 is meshed with. Then the toothed drive belt
15 is rotated in the direction of arrow D in FIG.
The print head 8 is returned to and moved in the direction of arrow E integrally therewith and stopped at the left print start position. Then, when the carriage body 5 is returned, the rotation of the drive gear 33 is changed to the large diameter gear.
44, the small-diameter gear 45, the planetary gear 49, and the second driven gear 23 are transmitted to the second spool shaft 21, and inside the multi-ribbon cassette 25 as the second spool shaft 21 rotates in the rewinding direction. At, the multi-thermal ribbon R on the take-up spool 26 is rewound onto the supply spool 27. Further, at this time, the protrusion of the ring spring 53 is accompanied by the clockwise rotation of the large diameter gear 44.
52 is moved in the direction of approaching the rotating arm 48.

By the way, since the number of teeth of the small diameter gear 45 is set to be smaller than the number of teeth of the large diameter gear 44, and both gears 44, 45 are configured to rotate integrally, when the carriage body 5 returns,
The amount of rotation of the second spool shaft 21 by the small-diameter gear 45 until the protrusion 52, which has moved by a predetermined amount, returns to the clockwise direction in FIG. The rotation amount of the second spool shaft 21 is smaller than the rotation amount of the second spool shaft 21 rotated by rotating the large diameter gear 44 and moving the projection 52 on the small diameter gear 45 counterclockwise in the figure. The ratio corresponds to the tooth number ratio of the large diameter gear 44 and the small diameter gear 45. Therefore, when the large diameter gear 44 is further rotated clockwise in the contact state of the protrusion 52 and the rotating arm 48,
The pivot arm 48 is pivotally arranged against the action of the spring 50 to the position shown by the chain line in FIG. 4, and the engagement between the second driven gear 23 and the planet gear 49 is released. Therefore, the multi-thermal ribbon R by the supply spool 27 when the carriage body 5 is returned
The rewinding amount of the multi-thermal ribbon R becomes smaller than the rewinding amount of the multi-thermal ribbon R by the take-up spool 26 at the time of immediately preceding printing. That is, the multi-thermal ribbon R capable of printing a large number of times in the one-line printing process is wound around the winding spool 26 at a constant rate, and as shown in FIG. It is possible to start from a position that is a predetermined distance away from the first printing point when printing,
By repeating these operations as the printing operation progresses, it is possible to carry out the printing of the allowable number of times of use at almost the same position of the multi-thermal ribbon R capable of printing many times. For example, when using a multi-thermal ribbon R capable of printing 10 times, if the tooth ratio of the large diameter gear 44 and the small diameter gear 45 is 10: 9, the ribbon winding amount in one line printing process is 9 / 10 is rewound.

Therefore, unlike the conventional thermal printer in which the entire length of the thermal ribbon is printed and then the ribbon cassette is removed from the carriage and is inverted and reloaded, there is no risk of inconvenience in handling the multi-ribbon cassette 25.

Moreover, if the amount of movement of the multi-thermal ribbon R associated with one printing operation is made equal to the amount of movement of the carriage body 5, the relative movement between the printing paper P on the platen 1 and the multi-thermal ribbon R can be prevented. There is no fear that the printing paper P is contaminated by the multi-thermal ribbon R during printing. Further, even when the outer shape of the take-up spool 26 of the multi-ribbon cassette 25 changes as the printing operation progresses and the take-up amount of the multi-thermal ribbon R changes, the large-diameter gear
Since the rewinding amount of the multi-thermal ribbon R by the supply spool 27 is always set to a constant ratio based on the tooth number ratio between the 44 and the small-diameter gear 45, the multi-thermal ribbon R can be sent over the entire length without any trouble. It can be used efficiently.

Next, the operation of the printing operation by the one-time thermal ribbon in which the one-time ribbon cassette 61 is mounted on the carriage body 5 and only one printing is allowed will be described. When the one-time ribbon cassette 61 is mounted on the carriage body 5 in the same manner as the multi-ribbon cassette 25, the cam portion 63 of the actuating protrusion 62 engages with the rotating arm 48 as shown in FIG. Then, the rotation arm 48 is rotated clockwise in the figure, and the planetary gear 49 becomes the second driven gear.
Dissociated from 23. When the printing operation is started in this state, the lever 36 moves to the first position as the print head 8 moves to the printing position, as in the case of the multi-ribbon cassette 25.
At the position shown in the figure, the rotation of the drive gear 33 is transmitted to the first spool shaft 18, and the one-time thermal ribbon is wound on the winding spool 26 of the one-time ribbon cassette 61.

Then, when printing of one line is completed and the carriage body 5 is moved back, the lever 36 is arranged at the position shown in FIG. 4 along with the movement of the print head 8 to the non-printing position.
41 is disengaged from the drive gear 33, the large diameter gear 44 is meshed with the drive gear 33, the intermediate gear 47 is separated from the second driven gear 23, and the rearward movement of the second arm portion 46 is followed. The rotating arm 48 is pulled by the action of the spring 50 in the counterclockwise direction in FIG. However, at this time, the actuating protrusion 62 of the one-time ribbon cassette 61 has entered the rear position of the rotating arm 48, whereby the counterclockwise rotation of the rotating arm 48 is restricted, and the planetary gear 49 moves to the second position. Driven gear 23
Is not meshed with. Therefore, the second spool shaft 21 and the supply spool 27 of the one-time ribbon cassette 61 are held in a stopped state, and the rewinding operation of the ribbon is not performed.

Therefore, when the next printing operation is started in this state, the ribbon is moved again in the winding direction from the state at the end of the previous printing, and the first printing is performed at the position adjacent to the final printing position during the previous printing operation. Is done. Thus, when the one-time ribbon cassette 61 is mounted, the one-time thermal ribbon is always transported in only one direction, and when the printing is completed over the entire length of the one-time ribbon cassette 61, the one-time ribbon cassette 61 is removed from the carriage body 5, and a new one-time ribbon cassette 61 is removed. The ribbon cassette 61 is replaced. Therefore, according to the thermal printer of this embodiment, the ribbon feeding mechanism can be easily switched between the multi-thermal ribbon type and the one-time thermal ribbon type by a simple structure in which the operating protrusion 62 is provided on the one-time ribbon cassette 61. Can be made. Moreover,
The rotating arm 48 that engages with the operation protrusion 62 constitutes a releasing means when the one-time ribbon cassette 61 is attached,
Since a part of the gear support mechanism when the multi-ribbon cassette 25 is mounted is also configured, the number of parts can be reduced and the structure of the ribbon feed mechanism can be simplified.

(Other Embodiment) The present invention is not limited to the configuration of the above-described embodiment, and when the one-time ribbon cassette 61 containing the one-time ribbon is mounted on the carriage body 5 in the above-described thermal printer configuration. The rotating arm 48
Even if the operating means for activating the driving gear 33 and the second spool shaft 21 to be disengaged is changed to the structure of each of the other embodiments described in the next paragraph and embodied, Similar effects can be obtained.

(1) In the embodiment shown in FIG.
Is a protrusion 66 fixedly provided on the lower surface of the front edge of the multi-ribbon cassette 64, and a notch portion on the carriage body 5 at a position corresponding to the protrusion 66, into which the tip of the rotating arm 48 can be fitted. And a cylindrical actuating member 68 having 67. The operating body 68 is supported by a support shaft 69 which is vertically fixed on the upper surface of the carriage main body 5 so as to be able to move up and down while being constantly urged upward via a spring 70, and at the time of lowering, it is rotated by the action of the spring 50. A slanted cam surface 71 is formed which allows the moving arm 48 to rotate counterclockwise in the figure and guides it to the notch 67. Also, in this embodiment, unlike the above-mentioned embodiment, the entire lower surface of the one-time ribbon cassette (not shown) accommodating the one-time thermal ribbon which allows only one printing is formed smooth, and the ribbon cassette The operating body 68 does not engage with the lower surface of the operating body 68 when it is mounted.

Therefore, when the one-time ribbon cassette is mounted on the carriage body 5, the actuating body 68 is at the upper position, and the tip end portion of the rotating arm 48 abuts on the outer peripheral surface of the actuating body 68, and the planetary gears. 49 and the second driven gear 23 are held in the disengaged state. On the other hand, when the multi-ribbon cassette 64 is mounted on the carriage body 5, the protrusion 66
The actuating member 68 is pushed down by the guide member, guided by the cam surface 71, the rotating arm 48 is fitted into the notch 67, and the planetary gear 49 is moved to the second position.
The driven gear 23 is held in a state where it can be engaged with and disengaged from.

(2) In the embodiment shown in FIG.
Is provided on the lower surface of the front edge of the multi-ribbon cassette 74 through the insertion hole 75, and is arranged on the carriage body 5 so as to correspond to the insertion hole 75, and the tip of the rotating arm 48 can be fitted. It is composed of a cylindrical actuating body 77 having a notch portion 76. The operating body 77 is supported by a spring 78 attached to the upper surface of the carriage body 5 so as to be able to move up and down, and the lower end outer peripheral surface of the operating body 77 moves the rotating arm 48 in the notch 76 with the action of the spring 50. A cam surface 79 for guiding the outside of the notch portion 76 against the above is formed in an inclined shape. Further, the lower side surface of the one-time ribbon cassette (not shown) is formed to be smooth, and the lower side surface of the one-time ribbon cassette engages with the operating body 77 to move it downward when the ribbon cassette is mounted.

Therefore, when the one-time ribbon cassette is mounted, the rotating arm 48 is guided by the cam surface 79 and is rotated in the clockwise direction in FIG.
The driven gear 23 is held in a disengaged state.
Further, when the multi-ribbon cassette 74 is mounted, the actuating body 77 is fitted in the fitting hole 75 to keep the actuating body 77 in a natural state, and the rotating arm 48 is prevented from being actuated by the actuating means 73. .

(3) The actuating means 81 in the embodiment shown in FIG. 9 has a fitting hole 83 which is transparently provided on the lower surface of the front edge of the one-time ribbon cassette 82, and has substantially the same construction as that of the other embodiment (1). And an actuation body 68. Further, the lower side surface of the multi-ribbon cassette (not shown) is formed to be smooth, and when the same ribbon cassette is mounted, the lower side surface acts on the operating member 68.
Is pushed down and the rotating arm 48 is fitted into the cutout portion 67. Therefore, when the multi-ribbon cassette is mounted, the planetary gear 49 and the second driven gear 23 are held in a meshable and disengageable state. On the other hand, when the one-time ribbon cassette 82 is mounted, the operating member is inserted in the fitting hole 83.
Since the 68 is fitted and is not lowered, the rotating arm 48 comes into contact with the outer peripheral surface of the actuating body 68 and the planetary gear 49 and the second driven gear 23.
And are held in a disengaged state.

The present invention is not limited to the configuration of the thermal printer described in each of the above embodiments, and a multi-ink ribbon cassette containing an ink ribbon capable of printing a large number of times and an ink that allows only one printing are printed. It is also possible to apply the present invention to a printing apparatus of the type configured so that a one-time ink ribbon cassette accommodating a ribbon can be exchanged for use.

As described above in detail, according to the present invention, the rewinding amount of the ribbon is configured to be smaller than the winding amount of the ribbon printed immediately before by a certain ratio, and only one printing is performed. The ribbon cassette that contains the acceptable ribbon is configured so that it will not be rewound when it is installed.Therefore, when using a ribbon that can be printed multiple times, you can flip the ribbon cassette and reload it. It can be eliminated, and there is no risk of the relative movement of the ribbon and the printing paper to contaminate the printing paper, and a ribbon feeding mechanism with one simple structure can print many times and a ribbon. It has an excellent effect that it can be easily exchanged and used with a ribbon which allows only the ribbon.

[Brief description of drawings]

FIG. 1 is a plan view of a main part of a printer embodying the present invention,
2 is a side sectional view of the main part of the printer, FIG. 3 is a plan sectional view showing a state in which a ribbon cassette is mounted, and FIG. 4 is a plan view of the main part in an operating state different from FIG. FIG. 6 is a perspective view of a main part showing the configuration of second and third releasing means and actuating means, FIG. 6 is a partial front view of a ribbon for explaining a printing action, and FIGS. 7 to 9 are different from each other. It is a principal part perspective view which shows another Example of an operating means. In the figure, 1 is a platen, 5 is a carriage body, 7 is a head carriage, 8 is a print head, 18 is a first spool shaft, 21 is a second spool shaft, 25, 64 and 74 are multi-ribbon cassettes, and 26 is a winding. The take-up spool, 27 is a supply spool, 33 is a drive gear, and 20, 39 and 41 are first driven gears, fixed position gears and displacement gears that constitute a first rotation transmission mechanism, 23, 44, 45 and 49.
Is a second driven gear, a large-diameter gear, a small-diameter gear and a planetary gear that constitute a second rotation transmission mechanism, 36 has a lever as a first releasing means, and 53 has a protrusion 52 as a second releasing means. A ring spring, 48 is a rotating arm as a third releasing means, 61 and 82 are one-time ribbon cassettes, 62 is an operating protrusion as an operating means, 65, 73 and 81 are operating means having different configurations, and R is It is a multi-thermal ribbon.

Claims (1)

[Claims] 1. A carriage (5, 7) movable along a platen (1), a printing position placed on the carriage (5, 7) and pressed against the platen (1), and a platen (1). ), A print head movable between a non-printing position and
And a ribbon cassette (25) detachably attached to the carriage (5, 7), wherein the carriage (5, 7) performs printing only when the carriage (5, 7) moves in one direction. Carriage (5,7) provided in 5,7)
Drive gear (33), which is rotationally driven by the movement of the tape, and a first spool shaft (18) for rotating the drive gear (33) and the take-up spool (26) of the ribbon cassette (25).
Is provided between the drive unit and the drive unit such that the first spool shaft (18) rotates in the winding direction of the ribbon (R) as the carriage (5, 7) moves in the one direction. The first for transmitting the rotation of the gear (33) to the first spool shaft (18)
Driven by the rotation transmission mechanism (20, 39, 41) and the print head (8), and when the print head (8) is located at the non-printing position separated from the platen (1), the first rotation transmission is performed. First releasing means (36) for releasing rotation transmission from the drive gear (33) to the first spool shaft (18) by the mechanism (20, 39, 41), the drive gear (33) and the ribbon cassette The second spool shaft (21) is provided between the supply spool (27) of (25) and the second spool shaft (21) that rotates, and the second spool shaft (21) is moved by the return movement of the carriage (5, 7). The ribbon (R) is rotated in the rewinding direction, and the amount of rotation is transmitted from the drive gear (33) to the first spool shaft (18) by the first rotation transmission mechanism (20, 39, 41). The rotation of the drive gear (33) is transmitted to the second spool shaft (21) so as to be smaller than the rotation amount at the time of Second rotation transmitting mechanism (23,44,45,4
9) and the first rotation transmission mechanism (20, 39, 41) so that the rewinding amount of the ribbon (R) becomes smaller than the winding amount of the ribbon (R) printed immediately before by a fixed ratio. ) And the second rotation transmission mechanism (23,44,4
5, 49) after connecting the rotation transmission by the second rotation transmission mechanism (23, 44, 45, 49) to release the rotation transmission from the drive gear (33) to the second spool shaft (21). 2 release means (52) and the second rotation transmission mechanism (23,44,45,49) release the rotation transmission from the drive gear (33) to the second spool shaft (21), and Third releasing means (4
8), a ribbon cassette (25, 61) mounted on the carriage (5, 7) and a third releasing means (48),
When a ribbon cassette (25) accommodating a ribbon (R) capable of printing a large number of times is mounted, the third releasing means (48) is invalidated, and a ribbon cassette (61) accommodating a ribbon allowing only one printing And a means (62, 65, 73, 81) for activating the third releasing means (48) when the printer is mounted.