JP2001026159A - Printing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To smoothly move a printing head in the longitudinal direction of a platen regardless of a page to be opened when data is printed on a booklet and to simplify a structure. SOLUTION: The printing head 7 energized toward a platen 5 is provided to a carriage 6 in a freely movable manner and a press surface having an inclined surface 14 riding on the printing medium S on the platen 5 from the platen 5 at a time of the movement of the carriage 6 to press the printing medium S is provided at the position along the front surface on the side of the platen 5 of the printing head 7 so as to keep the relative position to the printing head 7 constant. By this constitution, when data is printed on a booklet being the printing medium S, the printing head 7 is smoothly moved in the longitudinal direction of the platen 5 regardless of a page to be opened and a structure can be simplified.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus for printing information on a printing medium including a booklet.

[0002]

2. Description of the Related Art Conventionally, a print head such as an impact dot printer head or a thermal head is mounted on a carriage reciprocally driven along a platen, and the carriage is held in a state in which a print medium on the platen is pressed by the tip of the print head. 2. Description of the Related Art There is a printing apparatus that performs printing by moving along a print head along a longitudinal direction of a platen.

[0003] In the case of printing information on a booklet using such a printing apparatus, when the booklet is opened with the binding portion of the booklet orthogonal to the platen, the binding portion may be opened depending on the opened page. A step occurs due to the difference in the number of pages on both sides as the boundary. If the step is large, the print head receives a large resistance when moving from the side where the number of pages is small to the side where the number of pages is large.

[0004] For this reason, the platen is divided into a plurality of parts along the longitudinal direction, and each of the plurality of divided platens is biased toward the print head and independently supported so as to be able to advance and retreat. If the number of open pages causes a step difference due to a difference in the number of pages on both sides of the bound portion as described above, the portion having a larger number of pages is supported than the platen supporting the portion having a smaller number of pages. There is a platen structure in which the platen is retracted with respect to the print head, thereby maintaining the surface of the open page of the booklet substantially flat.

[0005]

However, as described above, the structure in which each of the plurality of divided platens is urged toward the print head and independently supported so as to be capable of independently moving forward and backward can precisely control the component accuracy. Therefore, there is a problem that the assembly adjustment work is troublesome and the manufacturing cost is increased.

An object of the present invention is to smoothly move the print head in the longitudinal direction of the platen irrespective of the page to be opened when printing information on a booklet, and to simplify the structure.

[0007]

According to the first aspect of the present invention,
A platen having a surface supporting the print medium continuous along the width direction of the print medium, a carriage reciprocally driven along the platen, and a print head provided on the carriage so as to be movable in a direction orthogonal to the platen A head urging means for urging the print head toward the platen, and a fixed position is fixedly provided along a front surface of the print head on the platen side while a relative position with respect to the print head is kept constant. And a pressing surface that has an inclined surface that rises from the platen to the surface of the print medium on the platen when the carriage moves, and that presses the print medium on the platen.

Accordingly, the pressing surface that maintains a fixed positional relationship with the print head presses the platen or the print medium supported by the platen. When the print medium is fed onto the platen and the carriage is moved from the non-print area at the end of the platen where the print medium does not exist to the central print area where the print medium exists, the pressing surface should be inclined on the print medium. The print head and the pressing surface are retracted from the platen by the amount of the ride. This makes it possible to maintain a constant relative position between the print surface of the print medium and the front surface of the print head, even if the number and thickness of the print media are different. Further, even when the print medium is a booklet and the number of open pages of the booklet causes a step due to a difference in the number of pages on both sides of the binding section, the print head is smoothly moved in parallel with the platen together with the carriage. Can be moved.

According to a second aspect of the present invention, in the first aspect of the invention, the head biasing means supports the print head and is movable on the carriage so as to be movable in a direction orthogonal to the platen. And a biasing member for biasing the movable support in the platen direction.

Accordingly, the print head moves with respect to the platen together with the movable support in accordance with the thickness of the print medium on the platen.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings. 1 is a front view showing a state in which the carriage is located at an end of the platen, FIG. 2 is a side view showing a state before the print medium reaches the platen, and FIG. 3 is a print medium in which the pressing surface of the print head is on the platen. 4 is a side view showing a state in which the print medium has passed through a platen.

As shown in FIG. 1, opposed side plates 1, 2
Carriage shafts 3 and 4 and a flat platen 5 are installed in parallel. A carriage 6 is slidably supported by carriage shafts 3 and 4. An impact dot printer head 7 as a print head is provided on the carriage 6 so as to be movable in a direction orthogonal to the platen 5.

Although the impact dot printer head 7 may be provided directly on the carriage 6, it is mounted via the movable support 8 in the present embodiment. That is, the impact dot printer head 7 is fixed to the movable support 8 by screws 9, and the movable support 8 is supported by guide shafts 10 provided on both sides of the carriage 6 so as to be movable in a direction orthogonal to the platen 5.
A part of the guide shaft 10 connects the movable support 8 to the platen 5.
It is covered by a coil spring 11 as an urging member that urges the side. The upper end of the coil spring 11 is compressed by a protrusion 6a formed integrally with the carriage 6, and the lower end of the coil spring 11 urges the movable support 8 toward the platen 5. Here, the movable support 8 supporting the impact dot printer head 7 and the coil spring 11
Head biasing means 12 for biasing the impact dot printer head 7 toward the platen 5 is configured.

The movable support 8 has a frame-shaped protrusion 13 protruding toward the platen 5 side.
A pressing surface 15 for holding the printing medium S on the platen 5 is formed integrally with the inclined surfaces 14 on both sides of the surface of the printing medium S on the platen 5 from the surface of the platen 5 during the movement. Therefore, the relative position between the pressing surface 15 and the impact dot printer head 7 is always kept constant. Note that the pressing surface 15 having the inclined surface 14 may be provided at the tip of the impact dot printer head 7. 1
Reference numeral 6 denotes a guide plate for guiding the print medium S conveyed by a conveying member (not shown).

Although not shown, pulleys are provided in the vicinity of the side plates 1 and 2, one of which is driven by a carriage motor rotatable in forward and reverse directions, and a timing belt 17 (see FIGS. 4) is fixed to the carriage 6. That is, the carriage 6 is configured to be driven reciprocally along the platen 5 by driving the carriage motor.

Further, the printing apparatus according to the present embodiment includes an ink ribbon cartridge (not shown) for running the ink ribbon along the front surface of the impact dot printer head 7 and a thin plate separating the ink ribbon and the printing medium S. And a ribbon guide. The ribbon guide is provided with a window hole for passing a wire projecting from the front surface of the impact dot printer head 7 to the platen 5 side.

In such a configuration, as shown in FIG. 1, with the carriage 6 positioned at the non-printing area (home position) at the end of the platen 5, the print medium S is placed on the platen 5 and the impact dot printer head. 7 is conveyed. In this state, as shown in FIGS. 1 and 2, the impact dot printer head 7 and the movable support 8 advance by the urging force of the coil spring 11 until the pressing surface 15 contacts the surface of the platen 5.

After the printing medium S is fed onto the platen 5, the carriage 6 is moved to a printing area at the center of the platen 5 for printing. At this time, the pressing surface 15 rides on the printing medium S on the platen 5 from the surface of the platen 5 on the inclined surface 14, and as shown in FIG. With the head 7 retracted from the platen 5, the front surface of the impact dot printer head 7 coincides with the surface of the print medium S. When printing is completed and the print medium S passes through the platen 5 as shown in FIG. 4, the impact dot printer head 7 is moved to a position where the pressing surface 15 contacts the surface of the platen 5.
And the movable support 8 advance by the urging force of the coil spring 11.

At the time of printing, as shown in FIG. 1, when the printing medium S is a booklet, a step S due to a difference in the number of pages on both sides of the binding portion Sa depending on the number of opened pages of the booklet.
b, the impact dot printer head 7 and the movable support 8 are
The platen 5 is retracted by an amount corresponding to the number of pages of the upper booklet. At this time, the pressing surface 15 smoothly passes through the step Sb in order to climb from the portion having a small number of pages to the portion having a large number of pages on the inclined surface 14. When the carriage 6 moves in the opposite direction, the pressing surface 15 goes down from a portion having a large number of pages to a portion having a small number of pages, so that the resistance from the step Sb is small and passes smoothly.

In order to obtain such an effect, the impact dot printer head 7 is provided on the carriage 6 so as to be movably urged toward the platen 5. However, when the impact dot printer head 7 is provided directly on the carriage 6. However, as in the present embodiment, the impact dot printer head 7 is connected to the carriage 6 via the movable support 8.
However, the configuration in which one impact dot printer head 7 or the movable support 8 is movably supported in one direction can be achieved by urging each of a plurality of platens in the direction of the impact dot printer head 7 as in the related art. The structure can be simplified as compared with a structure in which the structure is independently movably supported.

Further, the present invention is not limited to a printing apparatus using the impact dot printer head 7,
The present invention is also applicable to a printing apparatus using another print head including a thermal head.

[0022]

According to the first aspect of the invention, the print head biased toward the platen is movably provided on the carriage, and the carriage is moved to a position along the front surface of the print head on the platen side. At times, a pressing surface that presses the print medium from the platen with an inclined surface that runs over the print medium on the platen is provided while maintaining the relative position with respect to the print head constant, so that the print medium is fed onto the platen, and the print medium is When moving the carriage from the non-printing area at the end of the non-existent platen to the central printing area where the print medium is present, the press surface is raised on the print medium on the inclined surface, and the print head is moved by that amount. And the pressing surface can be retracted from the platen. Thus, even if the number and thickness of the print media are different, the relative position between the print surface of the print medium and the front surface of the print head can be kept constant. Further, even when the print medium is a booklet and the number of open pages of the booklet causes a step due to a difference in the number of pages on both sides of the binding section, the print head is smoothly moved in parallel with the platen together with the carriage. Can be moved. Such an effect can be obtained by biasing the print head toward the platen side of the carriage so as to be movable, so that the structure can be simplified.

According to the second aspect of the present invention, the head urging means includes a movable support mounted on the carriage so as to support the print head and to be movable in a direction perpendicular to the platen, and to move the movable support to the platen. The print head moves forward and backward with respect to the platen together with the movable support in accordance with the thickness of the print medium on the platen. Thereby, the same effect as the first aspect can be obtained.

[Brief description of the drawings]

FIG. 1 illustrates an embodiment of the present invention, and is a front view illustrating a state where a carriage is located at an end of a platen.

FIG. 2 is a side view illustrating a state before a print medium reaches a platen.

FIG. 3 is a side view showing a state in which a pressing surface of a print head presses a print medium on a platen.

FIG. 4 is a side view showing a state in which a print medium has passed a platen.

[Explanation of symbols]

 S Print medium 5 Platen 6 Carriage 7 Print head 8 Movable support 11 Urging member 12 Head urging means 14 Inclined surface 15 Pressing surface

Claims (2)

[Claims] 1. A platen having a surface supporting a print medium continuous in the width direction of the print medium; a carriage reciprocally driven along the platen; and a carriage movably movable in a direction orthogonal to the platen. A print head provided, head biasing means for biasing the print head toward the platen, and a position relative to the print head being maintained constant and fixed along a front surface of the print head on the platen side. And a pressing surface that has a sloped surface that rises from the platen to the surface of the print medium on the platen when the carriage moves and that presses the print medium on the platen. 2. A head urging means, comprising: a movable support mounted on the carriage so as to support the print head and move in a direction perpendicular to the platen; and bias the movable support in the platen direction. The printing device according to claim 1, further comprising: an urging member that performs the operation.