JPH0517252Y2 - - Google Patents

Description

[Detailed description of the invention] Purpose of the invention (industrial application field) This invention relates to a printing device, and in particular, when the carriage moves laterally on the guide means, the printing head mounted on the carriage prints on the platen. The present invention relates to a printing device that prints on paper.

(Prior Art) Conventionally, in this type of printing device, a support arm with a print head supported and fixed at its tip is rotatably supported on a carriage at its base end, and the tip of this support arm is always It is known that the support arm is placed in a retracted position away from the platen, and during printing, the tip of the support arm is rotated to the printing position where it approaches the platen, so that printing is performed by the printing head. .

(Problems to be solved by the invention) However, in this conventional printing device, there is play in the assembly of the support arm to the carriage,
Due to deformation of the carriage itself, when the tip of the support arm is rotated to a printing position close to the platen, the printing head may not be aligned with the predetermined printing line on the platen and may shift vertically. There was a problem that this problem easily occurred and accurate printing could not be performed.

Further, in printing devices equipped with a correction function, there is a problem in that the print head is not placed in accurate correspondence with the characters, etc. on the printing paper to be corrected, making it impossible to perform the correction operation reliably. This problem during printing and collection was particularly noticeable when the carriage was molded from synthetic resin.

Structure of the invention (means for solving the problem) This invention was made by paying attention to the above-mentioned problems, and includes a horizontally extending platen 1.
and a guide means 2 parallel to the platen 1,
3 and a carriage 5 movably supported on the guide means 2, 3 and carrying a printing head 11, when the carriage 5 moves laterally on the guide means 2, 3, the printing head 11 In a printing device configured to print on printing paper on a platen 1, a support shaft supported by an end of a carriage near the platen and whose axis is oriented in the vertical direction, and a support shaft supported by the support shaft, A support arm that is rotatable in a substantially horizontal plane, a print head that is fixed to the tip of the support arm, and that moves closer and further away from the platen as the support arm rotates; Positioning means 22 and 27 are provided so as to be engageable between the distal end of the support arm 9 and the carriage 5, and for regulating the vertical position of the distal end.

(Function) Therefore, in the printing device of this invention, when the tip of the support arm approaches the platen, the vertical position of the tip of the support arm is regulated by the engagement of the positioning means, and the printing head is positioned above the platen. The print line is precisely aligned with the predetermined print line without any misalignment, and it is possible to always perform accurate printing and collection regardless of play in the assembly of the support arm to the carriage or deformation of the carriage itself. .

(Example) Hereinafter, an example of a printing device embodying this invention will be described in detail with reference to the drawings.

As shown in FIGS. 1 to 6, in the printing apparatus of this embodiment, a platen 1 extending laterally is supported on the rear side of a frame (not shown).
Below and in front of the platen 1, a metal guide rod 2 constituting a guide means and a guide rail 3 having a substantially horizontal U-shape in cross section are arranged parallel to the platen 1. A rack 4 is formed over the area. A synthetic resin carriage 5 is supported at the rear edge of the guide rod 2 so as to be movable in the left-right direction, and is slidably supported at the lower rear edge of the guide rail 3 at its front edge. An ink ribbon cassette 6 is removably supported on the carriage 5 via a cassette holder 7, and an ink ribbon 8 is stored inside the carriage 5. A part of the ink ribbon 8 is placed on the rear side of the ink ribbon cassette 6. It is being driven exposed to the outside.

As shown in FIGS. 1, 3 and 4, the platen 1
A support shaft 10 is erected on the carriage 5 at a portion (rear part) adjacent to the support shaft 10 so that its axis is directed in the vertical direction. A support arm 9 is attached to the support shaft 10.
is supported rotatably in a substantially horizontal plane at its base end, and a printing head 11 consisting of a thermal head is supported and fixed on the rear surface of its distal end.
A substantially chevron-shaped cam portion 12 is provided protruding from the front surface of the tip. As the support arm 9 rotates, the print head 11 moves toward the platen 1 shown in solid line in FIG.
The printing head 11 is arranged at a printing position close to the platen 1 and at a retracted position away from the platen 1 shown by the chain line in the same figure, and is arranged at the printing position as shown in FIG. Printing is performed on the printing paper on the platen 1 via the printing section.

so as to surround the base end of the support arm 9,
A rotating arm 13 is attached to the support shaft 10 at its base.
Rotatably supported at the letter-shaped bent portion 13a,
A pinch roller 14 for collection is rotatably attached to the upper surface of its tip. and,
As the rotating arm 13 rotates, the pinch roller 14
The pinch rollers 14 are arranged at an active position close to the platen 1, shown by a chain line in FIG. At the same time, the printing head 11 is placed at the printing position, and the external running portion of the ink ribbon 8 is connected to the platen 1.
With the surface in contact with the printing paper above, press print head 1.
1, characters and the like on the printing paper are peeled off and corrected via the ink ribbon 8.

That is, the ink ribbon 8 in this example
has an ink layer that is non-viscous at room temperature, melts and transfers at a predetermined high temperature or higher, and produces adhesive strength at an intermediate temperature. Therefore, the ink ribbon 8, which has been once heated to the predetermined high temperature by the print head 11, is cooled to the intermediate temperature while running in surface contact with the printing paper by the action of the pinch roller 14, thereby increasing the adhesive strength. When the characters on the printing paper are generated and separated from the printing paper at the position of the pinch roller 14,
That is, the ink is peeled off.

As shown in FIGS. 3 and 6, an actuating arm 15 is fixedly protruding from the central front surface of the support arm 9.
A cam follower 16 is rotatably supported on the upper surface of the bent intermediate portion. A spring 17 is provided between the tip of the operating arm 15 and the carriage 5, and rotates the support arm 9 clockwise in FIG. 3 to bias the print head 11 toward the printing position. . Further, the bent portion 13a of the rotating arm 13
An operating arm 18 is formed protruding from the lower front part of the
A cam follower 19 is rotatably supported on the upper surface of the bent intermediate portion. A spring 20 is provided between the tip of the operating arm 18 and the carriage 5, and rotates the rotating arm 13 clockwise in FIG. 3 to bias the pinch roller 14 toward the operating position. There is.

As shown in FIGS. 3 and 4, the print head 11
The flexible cable 21 connected to the support arm 9 is extended to the right along the rear surface of the support arm 9, goes around the base end of the support arm 9 between the bent portions 13a of the rotating arm 13, is guided forward, and is guided downward. and is connected to a control board, etc. (not shown). Therefore, as in the case where the flexible cable 21 is directly extended downward from the printing head 11, there is a space below the tip of the support arm 9 over the entire rotation range of the tip. Since there is no need to form a 100 mm diaphragm, the structure on the carriage 5 can be made compact.

As shown in FIGS. 1 to 4, a metal positioning pin 22 constituting positioning means is provided at the lower end of the support arm 9 to protrude leftward. Near the attachment point of the carriage 5 to the guide rod 2, a metal positioning plate 23 is vertically positioned on the inner surface of the left side wall of the carriage 5 via a support ridge 24, and is fixed by a mounting plate 25 and mounting screws 26. has been done. The positioning plate 23 has a positioning groove 2 constituting a positioning means.
7 is formed to extend in the front-rear direction, and a wide entrance portion 27a is provided at the front edge thereof. When the printing head 11 is moved from the retracted position shown by the chain line in FIG. 1 to the printing position shown by the solid line as the support arm 9 rotates, the positioning pin 22
is inserted into and engaged with the positioning groove 27 of the positioning plate 23, so that the vertical position of the print head 11 is regulated. Further, in this embodiment, since the print head 11 is positioned with reference to the guide rod 2, the positioning plate 23 is disposed near the attachment part of the carriage 5 to the guide rod 2, thereby facilitating the positioning accuracy of the print head 11. Moreover, it is possible to take it out reliably.

As shown in FIGS. 3, 5, and 6, a support shaft 28 is erected and fixed on the carriage 5 in front of the support arm 9 and the rotating arm 13, and a cylindrical worm wheel 29 rotates around the outer circumference of the support shaft 28. Possibly supported. A first actuating cam 30 having a substantially fan-shaped plane is integrally formed at the lower end of the worm wheel 29, and a cam follower 16 on an actuating arm 15 extending from the support arm 9 is engaged with the outer periphery of the first actuating cam 30. . Further, a second operating cam 31 having a larger diameter than the first operating cam 30 and having a generally fan-shaped plane is fitted and fixed to the upper end of the worm wheel 29.
A cam follower 19 on an actuating arm 18 extending from the pivot arm 13 engages with its outer periphery.

As shown in FIGS. 5 to 7, a drive shaft 32 with a non-circular cross section extending in the left-right direction is rotatably supported on the carriage 5 behind the worm wheel 29. A worm 33 that meshes with the worm 33 is slidably inserted therein, and the worm 33 is prevented from moving from side to side by ribs (not shown) on the carriage 5. Therefore, as the carriage 5 moves, the worm 33 moves on the drive shaft 32. is moved and always has a worm wheel 29
are placed facing each other. A motor (not shown) is operatively connected to the drive shaft 32, and the motor drives the drive shaft 3.
2. The first and second operating cams 30 and 31 are rotationally driven via the worm 33 and the worm wheel 29. And always the third
As shown in the figure, both cam followers 16, 19 engage the first and second actuating cams 30, 31, and the print head 11 is held in the retracted position against the action of the spring 17. Pinch roller 14 is connected to spring 20
When both actuating cams 30, 31 are rotated clockwise by a predetermined angle from this state, the cam follower 16 returns to the first actuating position as shown in FIG. 8a. It is separated from the cam 30, and only the printing head 11 is moved to the printing position by the action of the spring 17, and is in the printing state, and both operating cams 30 and 31 are rotated counterclockwise by a predetermined angle from the state shown in FIG. 8b, both cam followers 16 and 19 separate from the first and second operating cams 30 and 31, respectively, and the print head 1
1 is moved to the printing position by the action of the spring 17, and the pinch roller 14 is moved to the action position by the action of the spring 20 to enter the collection state.

As shown in FIGS. 5 to 7, a rotary cylinder 34 is rotatably and vertically movably inserted and supported on the support shaft 28 on the worm wheel 29, and a clutch disc 35 is formed protruding from the outer periphery of the rotary cylinder 34. ing.
A take-up joint 36 is attached to the upper end of the rotary cylinder 34, and engages with the take-up spool 37 in the ink ribbon cassette 6, and as the rotary cylinder 34 rotates, the take-up spool 37 is attached to the ink ribbon 8. It is designed to rotate in the winding direction. A drive gear 38 is fitted into the outer periphery of the rotary cylinder 34 below the clutch disk 35 so as to be relatively rotatable and movable up and down, and a support disk 39 is fitted so as to be integrally rotatable and movable up and down. A clutch body 40 made of felt or the like that can come into contact with the drive gear 38 is fixed to the upper surface of the support disk 39 and the lower surface of the clutch disk 35.

A spring seat 41 is fitted and supported on the outer periphery of the rotating cylinder 34 below the support disk 39 so as to be able to rotate integrally with the engagement of the claw portion 34a. 42 is interposed.
The clutch disc 35, the support disc 39,
An overload clutch 43 is constituted by the clutch body 40 and the like, and the rotation of the drive gear 38 is always transmitted to the rotary cylinder body 34 via the overload clutch 43, and the drive gear 38 rotates faster than the rotary cylinder body 34. When this happens, the operative connection by the overload clutch 43 is cut off.

As shown in FIGS. 5 to 7, an annular rotating plate 44 is fitted and supported on the outer periphery of the support disk 39 so as to be relatively rotatable, and a chevron-shaped cam portion on the support arm 9 is attached to the outer periphery of the annular rotating plate 44. 12, an engaging protrusion 44a, a support protrusion 44b, and a spring locking piece 44c are formed to protrude. A spring 45 is hung between the spring latching piece 44c of the rotating plate 44 and the carriage 5, and urges the rotating plate 44 to rotate clockwise in FIG. 7. The drive gear 3 is mounted on the support protrusion 44b of the rotating plate 44.
A transmission gear 46 meshing with the gear 8 is rotatably supported, and a pinion 47 that can engage and disengage from the rack 4 on the guide rail 3 is integrally formed on its upper surface.

As shown by the solid line in FIG. 7, when the print head 11 is placed in the retracted position, the cam portion 12 on the support arm 9 engages with the engagement protrusion 44a, and the rotating plate 44 springs. 45, the pinion 47 is placed in the rotational position shown by the solid line in the figure.
When the printing head 11 is moved to the printing position as shown by the chain line in FIG. The rotating plate 44 is rotated clockwise in the figure by the action of the spring 45, so that the pinion 47 engages with the rack 4.

Therefore, the printing state shown in FIG. 8a and FIG. 8b
In the collection state shown in
Only when the pinion 47 is moved to the right by a motor (not shown) or the like, the engagement between the pinion 47 and the rack 4 induces the pinion 47 to rotate clockwise in FIG. gear 3
8. The load is transmitted to the take-up joint 36 via the overload clutch 43 and the rotating cylinder 34, and the take-up spool 37 is rotated in the direction in which the ink ribbon 8 is taken up. Note that when the winding diameter of the ink ribbon 8 on this winding spool 37 increases, the winding spool 37
Even if the ink ribbon 8 is rotated at a constant speed as the carriage 5 moves, the winding speed of the ink ribbon 8 gradually increases. However, in this embodiment, the overload clutch 43 is provided in the winding rotation transmission path as described above. 8a and 8b, the ink ribbon 8 slips at the clutch 43, causing the ink ribbon 8 to
As shown in FIG. 2, when the print head 11 at the print position is pressed against the printing paper on the platen 1 and frictionally engaged with it, as the carriage 5 moves to the right, the print head 11 at the printing position constantly moves relative to the printing paper at the same speed as the moving speed of the carriage 5. The vehicle will be moved to the left.

Now, since the printing device of this embodiment is constructed as described above, when the printing head 11 is moved to the printing position as shown in FIG. 8a and printing is performed, or as shown in FIG. As shown in FIGS. 1 and 2, when the printing head 11 is moved to the printing position and the pinch roller 14 is moved to the operating position to perform correction, the tip of the support arm 9 is positioned as shown in FIGS. 1 and 2. The pin 22 engages with the positioning groove 27 of the positioning plate 23 on the carriage 5, and the vertical position of the print head 11 is regulated. Therefore, there is no play in assembling the support arm 9 to the carriage 5 or the carriage 5
Regardless of the deformation of the print head 11, the print head 11 is always placed in accurate correspondence with a predetermined print line on the platen 1, and the printing on the print paper on the platen 1 and the collection of characters, etc. on the print paper can be performed without misalignment. It can be done reliably.

It should be noted that this invention is not limited to the configuration of the above-mentioned embodiments, and it is also possible to embody the invention by changing the configuration of each part arbitrarily within a range that does not depart from the spirit of this invention.

Effects of the invention As detailed above, according to this invention, when the tip of the support arm approaches the platen, the vertical position of the tip of the support arm is regulated by the engagement of the positioning means, so that the printing head can move toward the platen. It is arranged to accurately correspond to the specified printing line above without causing positional deviation, and it is possible to always perform accurate printing and collection regardless of play in the assembly of the support arm to the carriage or deformation of the carriage itself. It has excellent effects.

[Brief explanation of the drawing]

Fig. 1 is a partial plan view showing an embodiment of a printing device embodying this idea, and Fig. 2 is an A-A in Fig. 1.
3 is a partially reduced plan view showing the configuration of the operating cam for operating the support arm and the rotating arm, FIG. 4 is a partial rear view of FIG. 3, and FIG. FIG. 6 is a partially enlarged sectional view taken along line C-C in FIG. 3, FIG. 7 is a partially enlarged sectional view taken along line D-D in FIG. 6, and FIG. 8a and 8b are partial plan views corresponding to FIG. 3, showing the operating state of printing and collection. DESCRIPTION OF SYMBOLS 1... Platen, 2... Guide rod constituting the guide means, 3... Guide rail constituting the guide means, 5... Carriage, 9... Support arm, 10... Support shaft, 11... Printing head, 22 …
...Positioning pin 23 constituting the positioning means...
...Positioning plate, 27...Positioning groove constituting positioning means.

Claims (1)

[Claims for Utility Model Registration] 1. A platen 1 extending in the horizontal direction, guide means 2 and 3 parallel to the platen 1, and a print head 11 movably supported on the guide means 2 and 3; A printing device comprising a carriage 5 mounted thereon, in which printing is performed on printing paper on the platen 1 by the printing head 11 when the carriage 5 moves laterally on the guide means 2 and 3. A support shaft 10 is supported at an end near the platen 1 of No. 5 and whose axis is directed in the vertical direction.
a support arm 9 supported by the support shaft 10 and rotatable in a substantially horizontal plane; and a support arm 9 fixed to the tip of the support arm 9 and moved toward and away from the platen 1 as the support arm 9 rotates. The printing head 11 and at least the distal end of the support arm 9 are provided at the distal end of the support arm 9 and the carriage 5 so that they can engage with each other when the distal end of the support arm 9 approaches the platen 1. A printing device characterized by comprising: positioning means 22 and 27 for regulating the position. 2. The printing device according to claim 1, wherein the positioning means 27 on the carriage 5 side is provided in the vicinity of the mounting portion of the guide means 2 of the carriage 5.