JPS6294370A - Thermal transfer printer - Google Patents

Abstract

PURPOSE:To reduce the number of drive sources required for realizing a head-up/head-down function and a paper-feeding function, by a method wherein turning of a switching lever and engagement of a paper-feeding lever with a ratchet are performed through the movement of a movable body by driving a motor. CONSTITUTION:A switching lever 24 is provided at its end part with a pin 25 to be engaged to an upper surface part inclusive of a cam 21 of a rack 20, and a head-up/head-down mechanism for shifting up a thermal head 18a toward a platen 37 or shifting down the head 18a away from the platen 37 comprises a main shaft 26 roughly elliptic in cross section, a support 18b, a cam 47, a spring 46 and the like. A carriage-moving mechanism for moving a carriage 18 along the platen 37 is constituted of gears 11, 13, a pulley gear 14, a pulley 15, a belt 17 and the like. A paper-feeding mechanism for feeding a recording paper to a printing position is constituted of a paper-feeding lever 27, a ratchet 29, a paper-feeding roller shaft 3, a rubber roller 34 and the like.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a thermal transfer printer that melts ink on an ink ribbon and transfers it to recording paper by heating a thermal head.

[Conventional technology]

Conventionally, this type of thermal transfer printer has a head up-down mechanism that lowers (down) the thermal head so that it comes into pressure contact with the platen during printing, and raises (up) the thermal head away from the platen when not printing. Some devices are equipped with a paper feed mechanism that transports the recording paper placed on the front side during printing operations, and these head up-down mechanisms and paper feed mechanisms are each operated by separate drive sources, such as pulse motors. It is supposed to be done.

[Problem that the invention seeks to solve]

By the way, as mentioned above, conventional thermal transfer printers require two pulse motors to drive the head up/down mechanism and the paper feed mechanism, which means that there are many drive sources, and generally one pulse motor is required to drive the head up/down mechanism and the paper feed mechanism. There is a problem in that the manufacturing cost is high due to the high price of the product.

The present invention has been made in view of the actual situation in the prior art, and its purpose is to ensure head up-down functions and paper feeding functions equivalent to those of the conventional technology, and to reduce the number of drive sources that realize these functions. An object of the present invention is to provide a thermal transfer printer that can reduce the amount of damage.

[Means for solving problems]

To achieve this objective, the present invention comprises one motor;
A moving body such as a rack or gear that moves according to the drive of this motor, a carriage on which the thermal head is mounted and can move in the direction along the platen, and a carriage that rotates according to the movement of the moving body and moves the thermal head. A switching lever that moves toward and away from the platen, and a ratchet 1 installed on the paper feed roller shaft that feeds the recording paper, can be engaged with this ratchet and can be swung by a moving body. The structure is equipped with a paper feed lever.

[Effect]

With the above configuration, the rotation of the switching lever and the engagement of the paper feed lever with the ratchet are performed through the movement of the movable body driven by the motor, and the rotation of the switching lever causes the main shaft to rotate. The head can be moved up and down by the rotation of the paper feed lever, and the paper feed roller shaft can be rotated by the rotation of the ratchet by the paper feed lever to feed the paper.In other words, one motor can perform the functions necessary for the thermal transfer printer. can be secured.

〔Example〕

Hereinafter, the thermal transfer printer of the present invention will be explained based on the drawings.

Figures 1 to 6 (at, (bl, (cl, +d))
, (el is an explanatory diagram showing the first embodiment of the thermal transfer printer of the present invention, FIG. 1 is a plan view showing the schematic configuration, FIG. 2 is an exploded perspective view showing the drive unit, and FIG. 3 is a carriage mounting FIGS. 4 and 5 are a schematic side view showing the configuration, a perspective view and a plan view showing the engagement relationship between the groove and the pin provided in the carriage provided in the first embodiment, and FIG. 6 fa
) to (e) are explanatory diagrams showing operations in the first embodiment.

In these figures, especially in FIG. 1.2, the symbol ``■'' is a drive source, that is, a pulse motor, which is mounted on the chassis 2. 3
is a gear attached to the output shaft of the pulse motor 1, 4 is a gear that engages with this gear 3, and 5.6 is a gear that is integrally provided at the upper and lower parts of this gear 4. Integrated gear 4'
, 5.6 are mounted on a rocking plate 7 and rotatably attached to a shaft 8 protruding from the chassis 2. The shaft 8 constitutes the center of swing of the swing plate 7. A gear 9.10 is rotatably held on the rocking plate 7'' and is engaged with the gear 6 described above.

A gear 11 engages with the aforementioned gear 5, and is rotatably mounted on a shaft 12 protruding from the chassis 2. A gear 13 engages with the gear 11 and is rotatably held on the chassis 2.

A pulley gear 14 engages with the gear 13, and a pulley 15 is integrally provided with the pulley gear 14'. 1st
16 shown in the figure is a pulley rotatably provided on the chassis 2 part located on the opposite side of the boo IJ15, and 17 is a pulley that is rotatably provided on the chassis 2 part located on the opposite side of the boo IJ15.
5 and Boo IJ16 is a connected body, such as a belt. Both ends of this belt 17 are attached to a carriage 18 shown in FIG. Note that 18a shown in FIG. 1 is a thermal head mounted on the carriage 18;
8b is a rotatable holder that holds this thermal head 18a.

Reference numeral 20 denotes a movable body, such as a rack, which is movable along the vertical direction in FIG. 1, and has a cam 21 at its tip as shown in FIG. It has a toothed portion 22, and a lower toothed portion 23 that can be engaged with the gear 10 described above.

Reference numeral 24 denotes a switching lever, which has a pin 25 at its end that engages with the upper surface portion of the rack 20 including the cam 21, and is integrally attached to a main shaft 26 having an oval shape in cross section. Note that the main shaft 26 also serves as a guide shaft for guiding the movement of the carriage 18.

The carriage 18 described above also includes a lower body 18c guided by the main shaft 26, as shown in FIG. 3, for example.
The lower body 18d is movable relative to the lower body 18c, that is, movable in the direction toward and away from the platen 37. In addition, in FIG. 3, 46 is a two-part body 18d of the carriage 18.
47 is a means for converting rotation of the main shaft 26 into movement of the lower body 18d;
For example, a cam 48 spline-coupled to the main shaft 26 is formed in the lower body 18d, and is a recess into which a cam 47 can engage. Further, 60 is a groove formed in the lower body 18c, and 61 is a pin that is integrally provided in the two-part body 18d and is movably engaged in the groove 60. The groove 60 mentioned above is the 4.5th groove.
As shown in the figure, it has an outbound path 60a and a return path 60b, and has step portions 60C and 60d in the middle of the outbound path 60a and at the rear connecting point of the outbound path 60a and the return path 60b, respectively.

Returning to FIG. 1.2, reference numeral 27 denotes a paper feed lever rotatably mounted on the rack 20, and is biased by a spring (not shown) so that its tip 28 always faces upward.

This paper feed lever 27 has a tip 28 that is connected to the ratchet 2.
For example, when the rack 20 moves in the direction of arrow 30 in FIG.
8 engages with the ratchet 29, and the ratchet 29 receives the pressing force and rotates in the direction of the arrow 31 in FIG. When the ratchet 29 moves in the 32 direction, the tip 28 slides along the shape of the teeth of the ratchet 29, thereby preventing the ratchet 29 from rotating. Note that 28a is a pin that appropriately restricts the rotation of the lever 27, and can be engaged with the upper surface of the rack 20. 33 is a paper feed roller shaft to which the ratchet 29 is attached, and 34 shown in FIG.

Further, 35 shown in FIG. 1 is a trigger solenoid, and 36 is an actuator that is rotated by the trigger solenoid 35, engages with the swing plate 7, and restricts the swing of the swing plate 7. In addition, 37 shown in FIG. 1 is a platen around which recording paper (not shown) is wound, and 38 is a paper that guides the recording paper (not shown) so that it is smoothly inserted between the paper feed roller shaft 33 and the rubber roller 34. This is a feeding guide. Also, the first
39 shown in the figure is a ribbon cassette mounted on the carriage 18, and 40 is an ink ribbon stored in this ribbon cassette 39.

Head up/down operation in which the thermal head 18a is moved down in the direction closer to the platen 37 or raised in the direction away from the platen 37 by the switching lever 24 including the pin 25 mentioned above, the main shaft 26, the holder 18b1 cam 47, the spring 46, etc. The mechanism is configured. In addition, the gears 11 and 13, the pulley gear 14,
A carriage moving mechanism for moving the carriage 18 along the platen 37 is configured by the belt 17 and the like. In addition, the above-mentioned paper feed lever 2
7, a ratchet 29, a paper feed roller shaft 33, a rubber roller 34, and the like constitute a paper feed mechanism that transports the recording paper to the printing position.

In the first embodiment configured as described above, the following operations are basically performed by driving the pulse motor 1.

(i) When the trigger solenoid 35 is energized to rotate the actuator 36 and the pulse motor 1 is driven with the actuator 36 releasing the regulation of the swing plate 7, the gear 3 rotates, and the rotation of the gear 3 causes the pulse motor 1 to rotate. Accompanying gear 4.5.6
rotates integrally, and as gear 4 rotates, gear 9.10
rotates. At this time, for example, when gear 4 rotates clockwise in FIG. , the rack 20 moves in the direction of arrow 30 in FIG. As the rack 20 moves, the pin 25 of the switching lever 24 rides up from the lower part 21a of the cam 21 to the middle part 21b of the cam 21, as shown in FIG. The main shaft 26 integrally rotates in the direction of arrow 49 in FIG. 3, and the cam 47 integrally rotates in the same direction. upper body 18d of carriage 18
The wall surface of the recess 48 is pressed, and the upper body 18d is pressed against the spring 46.
The thermal head 18a moves in the direction of the arrow 50 against the force of the arrow 50, and the thermal head 18a moves away from the platen 37 as shown by the arrow 50 via the holder 18b, and enters the head-up state.

At this time, as the upper body 18d moves in the direction of arrow 50 in FIG. 3, the pin 61 moves along the outward path 60 of the groove 60 shown in FIG.
a and then crosses the step 60c.

Therefore, in this state, if the pulse motor 1 is reversed so that the rack 20 is returned in the direction of the arrow 32 in FIG.
0c, the head-up state is maintained while the pin 25 of the switching lever 24 is kept out of engagement with the cam 21 of the rack 20. In such a state, the paper is not fed, but by moving the carriage 18, the thermal head 18a is moved (tab) a predetermined distance in the same line as the first printed line on the recording paper, and the carriage is moved again. In 18 stop positions, another printing in the same line can be realized. Further, during such dubbing, the main shaft 26 is not subjected to rotational force or twisting moment transmitted via the switching lever 24, and unnecessary internal stress is not generated in the main shaft 26.

(ii) Further, when the rack 20 is further moved in the direction of arrow 30 in FIG. 2 from the state shown in FIG. 6(b), as shown in FIG.
), the pin 25 rides on the upper part 2IC of the cam 21 of the rack 20, during which time the switching lever 24 rotates counterclockwise in FIG. 2, and the main shaft 26 moves in the direction of arrow 49 in FIG. Rotate further. Then, paper feed lever 2
The tip 28 of the ratchet 29 engages with the teeth 29a of the ratchet 29, and as the rack 20 moves in the direction of the arrow 30 in FIG. As shown at 62, it rotates clockwise in the figure. The paper feed roller shaft 33 rotates together with the rotation of the ratchet 29, and the recording paper (not shown) held between the paper feed roller shaft 33 and the rubber roller 34 is fed, for example, by one line.

(iii) When the rack 20 further moves in the direction of the arrow 30 in FIG. 2 from the above state, the protrusion 28b of the paper feed lever 27 hits the teeth 29a of the ratchet 29, as shown in FIG. As a result, the paper feed lever 27 rotates in the counterclockwise direction shown in FIG.
The mesh with tooth 9 is released. That is, rack 20
The error in the amount of movement of the paper feed lever 27 can be absorbed by the shape of the protrusion 28b of the paper feed lever 27, and regardless of the error in the amount of movement of the rack 20, the engagement of the paper feed lever 27 and the ratchet 29 can be released at the optimum timing by the protrusion 28b. The recording paper (not shown) can be accurately advanced by, for example, one line.

In addition, in the state shown in FIG. 6 (dl, (el),
The switching lever 24 is in the most rotated state in the counterclockwise direction in FIG. 2, that is, the main shaft 26 and the cam 47 shown in FIG. The pin 61 of the upper body 18d is at the 4.5th position.
It is located near the innermost part of the return path 60b beyond the step 60d of the groove 6o shown in the figure.

(iv) During the transition from the state shown in Fig. 6 fa) to the state shown in Fig. 6 (el), the gear 3 shown in Fig. 1.2 rotates, the gears 4 and 5.6 rotate, and the gear 5 gear 11 engaged with
rotates, the gear 13 rotates, the pulley gear 14 rotates, the pulley 15 rotates, and the belt moves,
Along with this movement of the belt 17, the carriage 18 moves along the platen 37, and the carriage 18
As the ribbon cassette 39 and thermal head 1 move,
8a etc. move integrally. This allows carriage 1
For example, in addition to the above-mentioned tab movement, 8 moves to the home position (print start position) and enters a print standby state.

(v) From the state shown in FIG. 6(e) above, the pulse motor 1
When reversed, the swing plate 7 swings counterclockwise in FIG. 1 via the gear 3.4, which causes the gear 9 and the rack 2
As the rack 20 moves, the pin 25 of the switching lever 24 descends along the cam 21, and the switching lever 24 rotates clockwise in FIG. The shaft 26 rotates in the direction of arrow 49a in FIG.
7 rotates in the same direction, and by the force of the spring 46, the pin 61 shown in FIGS.
As a result, the upper body 18d moves in the direction of arrow 51, and the thermal head 18a moves in a direction approaching the platen 37 via the holder 18b, and finally reaches the head-down state shown by the solid line in FIG. Become. During this time, as the rack 20 moves in the direction of arrow 32 in FIG. 2, the tip 28 of the paper feed lever 27 slides on the teeth 29a of the ratchet 29, so the ratchet 29, that is, the paper feed roller shaft 33 does not rotate. Thereafter, the paper feed lever 27 separates from the ratchet 29 and enters the state shown in FIG. 6 (al).

In this state, by heating the thermal head 18a and moving the carriage 18, a predetermined portion of the ink ribbon 40 is melted by the thermal head 18a, and printing is performed on recording paper (not shown).

In the embodiment configured as described above, the rack 20 is moved by the drive of the pulse motor 1, the switching lever 24 is thereby rotated, the paper feed lever 27 is appropriately engaged with the ratchet 29, and the main The shaft 26 can rotate to move the head up and down, and the paper feed roller shaft 33 can rotate to feed paper.
That is, the head up/down and paper feeding can be performed by one pulse motor, and manufacturing costs can be reduced.

In the first embodiment, the rack 20 is provided with toothed portions 22 and 23 on the sides, and the rack 20 is moved via gears 9 and 10 that can be engaged with these toothed portions 22 and 23. However, the present invention is not limited to this.
As shown in the figure, a cam body 70 having the same external shape as the rack 20 is provided, a screw body 71 is integrally extended to this cam body 70, and a gear 72 is screwed onto this screw body 71. The gear 3 attached to the output shaft of the pulse motor 1 may be engaged with the gear 72.

Although not shown, the paper feed lever 27 described above is movably attached to the cam body 70, and the pin 25 of the switching lever 24 is attached to the cam body 70 in a movable manner.
can be engaged with the cam body 70.

With this configuration, when the gear 72 rotates due to the rotation of the gear 3 accompanying the drive of the pulse motor 1, the threaded body 71 is rotated by the threaded engagement between the gear 72 and the screw body 71.
, that is, the cam body 70 moves in the left-right direction in FIG.
As a result, head up/down and paper feeding operations similar to those described above can be carried out. FIG. 8 is a side view of a main part showing a second embodiment of the present invention. In this second embodiment, a gear 80 having teeth formed only on a part of its outer periphery is provided as a moving body in place of the rack 20 described above, and the teeth 81 are connected to the output shaft of the pulse motor 1, for example. It can be engaged with the attached gear 3. Further, the gear 80 has a cam 82 in the center, and this cam 82
2 is engaged with the pin 25 of the switching lever 24 mounted on the main shaft 26, and the paper feed lever 27, which can be held by a ratchet 29 attached to the paper feed roller shaft 33, can be swung by this gear 80. It is attached to. The paper feed lever 27 is biased, for example, by a spring (not shown) so that its tip 28 faces toward the ratchet 29.

In this second embodiment, when the gear 3 rotates as the pulse motor 1 is driven, the gear 80 rotates within the area where the teeth 81 are provided, and the cam 82 rotates accordingly. The switching lever 24 is connected via the pin 25 that engages the cam 82.
The main shaft 26 rotates to move the head up and down, and as the gear 80 rotates counterclockwise in the figure, the paper feed lever 27 moves to the ratchet 2.
9, the ratchet 29 rotates only in one direction, clockwise in the figure, and the paper feed roller shaft 33 rotates to carry out a predetermined paper feed.Moreover, the drive source is a single pulse motor. The manufacturing cost is low.

In the above embodiment, a pulse motor was used as the drive source, but a motor that can control positioning, such as a DC servo motor, can be used in the same way, and this case also has the effect of reducing the number of drive sources. is obtained.

〔Effect of the invention〕

Since the thermal transfer printer of the present invention is configured as described above, it is possible to ensure the same head up-down function and paper feeding function as conventional ones, and also to reduce the number of drive sources for realizing these functions. Manufacturing costs can be reduced compared to conventional methods.

[Brief explanation of drawings]

Figures 1 to 6 (a), (b), (cl, (di)
, (e) is an explanatory view showing a first embodiment of the thermal transfer printer of the present invention, FIG. 1 is a plan view showing the schematic configuration, FIG. 2 is an exploded perspective view showing the drive unit, and FIG. 3 is a carriage. FIGS. 4 and 5 are a schematic side view showing the mounting form, a perspective view and a plan view showing the engagement relationship between the groove and the pin provided in the carriage provided in the first embodiment, and FIG. 6 ia
) to (e) are explanatory diagrams illustrating the operation in the first embodiment, FIG. 7 is a side view of main parts showing another aspect of the moving body, and FIG.
The figure is a side view of essential parts showing a second embodiment of the present invention. 1... Pulse motor, 18... Carriage, 18a... Thermal head, 18c...
...Lower body, 18d... Upper body, 20...
... Rack (moving body), 24 ... Switching lever, 26 ... Main shaft, 27 ...
・Paper feed lever, 29...Ratchet, 33・
... Paper feed roller shaft, 37 ... Platen, 60 ... Groove, 61 ... Bin, 70.
...Cam body (moving body), 71... Screw body, 72... Gear, 80... Gear (moving body), 82... ·cam. Figure 3 Figure 4 Figure 6 DolσDolD Figure 7 Figure 8

Claims (3)

[Claims] (1) one motor, a moving body that moves according to the drive of this motor, a carriage on which a thermal head is mounted and can move in the direction along the platen, and a carriage that rotates according to the movement of the moving body, a switching lever that moves the thermal head toward and away from the platen;
A ratchet that is directly connected to the paper feed roller shaft that feeds the recording paper,
A thermal transfer printer characterized by comprising a paper feed lever which can be engaged with the ratchet and is swingably provided on the movable body. (2) The thermal transfer printer according to claim (1), wherein the moving body is a rack. (3) The movable body has a cam that engages with the switching lever, and is a rotatable gear.
The thermal transfer printer described in section 1).