JPH07736U - Printer - Google Patents

Abstract

(57) [Abstract] [Purpose] It is an object of the present invention to provide a printer that sandwiches a print sheet between a platen and a thermal head and prints on the print sheet, which printer can carry the print sheet smoothly. [Constitution] Platen base 13 to which platen 6 is fixed
14 holding the lower end of the platen guide base 16
The leaf spring 20 fixed to the back surface of the platen guide base 16 urges the
Is slightly tilted downward to which the printing paper 7 is fed.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a printer, and more particularly to a printer that prints on a printing paper by sandwiching the printing paper with a platen and a thermal head.

[0002]

[Prior art]

 As a relatively small printer used for printing such as a word processor, a serial printer that prints while moving a thermal head in the line direction is often used.

FIG. 4 shows a block diagram of a conventional printer of this type. In the figure, 31 indicates a thermal head. The thermal head 31 is movable together with the carriage 32 in the direction perpendicular to the paper surface. A ribbon cassette 34, around which an ink ribbon 33 is wound, is mounted on the carriage 32, and the ink ribbon 33 is wound up as the carriage 32 moves.

The thermal head 31 is rotatable in the direction of arrow F, and at the time of printing, it rotates in the direction of arrow F _{1 as} shown in FIG. 4B, and the platen 35 held by the platen holder 38. The ink ribbon 33 and the printing paper 36 are sandwiched and brought into close contact with each other.

The printing paper 36 is conveyed upward by rollers 37 and is arranged between the platen 35 and the thermal head 31. At this time, in a small printer, the printing paper 36 was conveyed while changing the conveying direction from the horizontal direction to the vertical direction in order to reduce the size.

Further, the platen 35 was held by the platen holding portion 38 from the beginning so as to face the thermal head 31 in order to improve the adhesion to the thermal head 31.

[0007]

[Problems to be solved by the device]

 However, in the conventional printer, the platen 35 is fixed or held in advance in the holding portion so that the platen 35 faces the thermal head 31 when the thermal head is pressed. As shown in (), the leading end portion of the printing paper 36 comes into contact with the side surface of the platen 35, and the printing paper 36 is bent or the printing paper 36 cannot be conveyed. .

The present invention has been made in view of the above points, and an object of the present invention is to provide a printer that can smoothly convey a printing sheet.

[0009]

[Means for Solving the Problems]

 The present invention relates to a printer for nipping a printing sheet by a platen held by a holding member so as to be aligned and a printing head for printing by pressing the platen, wherein the printing head of the platen is used. And a biasing means for biasing the platen so as to incline so that the surface facing to the print paper supply side is inclined.

[0010]

[Action]

 Since the surface of the platen facing the print head is inclined by the biasing means so as to face the side on which the print paper is supplied, when the print paper is supplied, the end of the print paper is printed by the platen. Abut on the surface facing the head at a shallow angle.

Therefore, the edge of the printing paper is smoothly fed while being guided in the ejection direction by the platen.

Further, when the printing head comes into close contact with the platen, it rotates in the ejecting direction of the printing paper due to its centering action, so that tension is exerted on the printing paper and wrinkles do not occur on the printing paper. The print quality can be improved.

Further, when the printing head comes into close contact with the platen, the platen is rotated against the urging force of the urging means, so that the collision force of the printing head with the platen can be mitigated, and therefore, , The operation sound can be reduced.

[0014]

【Example】

 FIG. 1 shows a block diagram of an embodiment of the present invention. In the figure, 1 indicates a thermal head. The thermal head 1 is connected to the carriage 2 and is configured to move together with the carriage 2 in a direction perpendicular to the paper surface of FIG.

Further, the thermal head 1 is configured to rotate in the arrow A direction by a head up / down mechanism 3 mounted on the carriage 2. An ink ribbon 4 is wound around the carriage 2 and an ink cassette 5 accommodated therein is mounted. The path of the ink ribbon 4 is set so as to come between the thermal head 1 and the platen 6, and when the thermal head 1 goes down, the thermal head 1 and the printing paper 7 and the platen 6 come into close contact with each other.

The printing paper 7 is pulled out from the tray 9 by the pull-out roller 8 and is conveyed upward through the one-way roller 10. Above the one-way roller 10, a counter roller 12 that faces the feed roller 11 and the feed roller 11 is disposed.

The printing paper 7 is conveyed between the one-way roller 10 and the feed roller 11 and the counter roller 12 while changing the conveying direction from the horizontal direction to the vertical direction. The counter roller 12 is rotated by a motor or the like, and the feed roller 11 is pressed against the counter roller 12, and the counter roller 12 is rotated to further convey the printing paper 7 upward. A platen 6 is arranged above the feed roller 11.

FIG. 2 is a block diagram of the essential parts of an embodiment of the present invention. In FIG. 2, (A) shows a back surface, (B) shows a top view, and (C) shows a front view.

The platen 6 is fixed to the surface of the platen base 13 with an adhesive or the like. Claws 14 and 15 are integrally formed at a plurality of upper and lower ends of the back surface of the platen base 13, and the claws 14 and 15 are formed on a platen guide base 16 which serves as a holding portion for holding the platen 6. It engages with engagement holes 17 and 18 formed corresponding to the claws 14 and 15.

The platen base 13 is urged in the direction of arrow B by a coil spring or the like provided at the end, and the urging force causes the claw portions 14 and 15 to engage with the engagement holes 17 and 18, and thus the direction of arrow C. It is prevented from being detached from the platen guide base 16, and is formed and held by being fitted into the concave portion 23 formed on the platen guide base 16. At this time, the recess 23 is formed to a depth such that the platen 6 slightly protrudes from the recess 23 of the platen guide base 16.

At this time, a convex portion 19 is formed on the surface of the platen guide base 16 facing the platen base 13 in the extending direction of the platen base 13 (direction of arrow X), and the platen base 13 is shown in FIG. It is configured to be swingable in the direction of arrow D, and is configured to perform centering so that the platen 6 is in close contact with the thermal head 1.

Further, a plate panel 20 which is a biasing means is fixed near the engaging hole 17 of the platen guide base 16. The leaf spring 20 has its tip portion 21 disposed between the platen guide base 16 and the lower claw portion 14 of the platen base 13.

The tip portion 21 of the leaf spring 20 is bent in the arrow E direction, and urges the lower claw portion 14 of the platen base 13 in the arrow E direction.

When the lower claw portion 14 of the platen base 13 is biased by the leaf spring 20 in the direction of arrow E, the surface of the platen 6 tilts slightly downward.

FIG. 3 shows a cross-sectional view of an essential part of an embodiment of the present invention.

Since the platen base 13 can be swung in the arrow D direction by the convex portion 19, when only the lower claw portion 14 is biased in the arrow E direction by the leaf spring 20, as shown in FIG. ), The platen base 13 is inclined, and the surface 22 of the platen 6 is slightly inclined downward.

By thus inclining the surface 22 of the platen 6 slightly downward, the contact angle θ between the surface of the platen 6 and the printing paper 7 is θ = 19 ° as shown in FIG. 3B, for example. And will contact at a shallow angle. Therefore, the printing paper 7 is less likely to be caught by the platen 6, and smooth transportation can be realized.

The surface 22 of the platen 6 faces slightly downward before the thermal head 1 comes into close contact, and when the thermal head 1 comes into close contact, the surface 22 rotates upward and comes into close contact with the thermal head 1. Therefore, when the platen 6 faces upward when the thermal head 1 is in close contact with the thermal head 1, the printing paper 7 is pulled upward, tension acts on the printing paper 7, and wrinkles do not occur. Therefore, the print quality can be improved.

Further, when the thermal head 1 comes into close contact with the platen 6, the platen 6 swings against the urging force of the plate spring 20. Therefore, when the thermal head 1 collides with the platen 6, the plate spring 20 As a result, the collision force is alleviated and the platen 6 comes into close contact with the platen 6. Therefore, the operation noise of the thermal head 1 when the thermal head 1 is down can be reduced.

[0030]

[Effect of device]

 As described above, according to the present invention, since the surface of the platen facing the printing head is inclined toward the side where the printing paper is fed, when the printing paper is fed, the end of the printing paper is First, it hits the surface of the platen facing the print head at a shallow angle and allows the printing paper to escape along the platen surface, causing the edges of the printing paper to catch on the platen, causing it to bend or become untransportable. The printing paper can be transported smoothly without any trouble, and when the print head is pressed by the platen, the platen rotates from the tilted state to the printing paper ejection direction by the centering action, so the printing paper Can be applied to the print head to improve the print quality. Moreover, when the print head is brought into close contact with the platen, the print head is pressed against the urging force of the urging means. Platen You can mitigate the impact force, thus, has a feature such as possible out to reduce the operation noise.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention.

FIG. 2 is a configuration diagram of a main part of an embodiment of the present invention.

FIG. 3 is an explanatory diagram of the operation of the main part of the embodiment of the present invention.

FIG. 4 is a configuration diagram of a conventional example.

[Explanation of symbols]

 1 Thermal Head 6 Platen 7 Printing Paper 13 Platen Base 14, 15 Claw 16 Platen Guide Base 17, 18 Engagement Hole 20 Leaf Spring

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masataka Okamura 1-4-4 Fujimi-cho, Gyoda-shi, Saitama Inside GEKO Co., Ltd.

Claims (1)

[Scope of utility model registration request] 1. A printer for performing printing by sandwiching a printing sheet between a platen held by a holding member so as to be aligned and a printing head for printing by pressing the platen, A printer comprising a biasing means for biasing the platen so that the surface facing the head is inclined so as to face the side on which the printing paper is supplied.